Thursday, 16 February 2017

The Lobster at Home

By Grant Allen
From Longman’s Magazine, July 1896.
Digitized by Doug Frizzle, Feb. 2017.

IT was, you will remember, the erroneous opinion of Alice (in Wonderland) that whiting were fish with their tails in their mouths. That biological mistake was a natural result of the culinary or purely domestic conception of animal life. In like manner, I believe, a great many people are still of opinion that lobsters are habitually and normally red—which is a rudimentary blunder of the same character as if one were to suppose that chickens swam in a sea of onion sauce as their native element, or that turkeys were infested with parasitic truffles. To combat such insufficient notions of crustacean life in the shallow seas it may be well to attend a lobster At Home off the coasts of Britain.
The common lobster who receives you in his rocky house is a ten-legged crustacean, with a large, powerful, and very muscular tail. This tail it is which marks off most distinctly the lobster group (including the crayfish, prawn, and shrimp) from their degenerate relations the mere crawling crabs, which are practically tailless. The difference in shape, again, is ultimately dependent upon a profound difference of habit and manner. All the lobster kind are more or less of swimmers, and they use their powerful tail with immense effect for jumping or darting through the water when disturbed, as well as for a gentler method of propulsion by fin-like flappers, to which I shall recur a little later. They may be regarded, in fact, from the point of view of habit, as great marine fleas; and this power of jumping or bounding through the sea is their most marked characteristic. The crabs, on the other hand, do not leap or swim in the adult condition; they merely crawl with a rather awkward motion along the bottom. Hence they have walking legs more developed than the lobster’s; their body is round, flat, and compressed; but the little shrivelled tail, reduced in their case to a bare shrunken relic, is doubled up under the body so inconspicuously that it probably altogether escapes the notice of the purely culinary or Epicurean observer. Both groups are descended from a common ancestor; but the crabs have taken so exclusively to walking that their tails have atrophied till they are reduced at last to mere sheaths for the eggs and other reproductive organs; while the lobsters and prawns have taken to jumping freely on the open, and used their tails so much that these leaping organs have at last developed into the largest and most important part of the animal.
Our English lobster is a beautiful, glossy, bluish-black creature, of iridescent sheen, with a scheme of colour not remotely reminding one of the mingled hues on the back of the swallow. Even when taken from the water his melting tints are very remarkable: but when seen at home, among his rocky haunts, and with the glaucous green glow of the sea shed lustrously over him, he is as magnificent a creature of his sort as nature has developed. When boiled, indeed, he turns at once to the vulgar and uniform red of the British soldier; but in his native state he is subtly and indescribably mottled with patches of dark blue and of cloudy black, which merge by imperceptible degrees into one another. Looked down upon through the water from above, he is seen among the crags as a black lurking mass, just projecting from a tunnel or crevice of the serpentine stacks, which he fits to a shade; whilst his front claws or crushers, his head and stalked eyes, and his tremulous antennae alone stand out on the watch for prey beyond the general surface of his sheltering rock-wall. But beheld on the level, as one sees him in the aquarium (which is, of course, the only fair way to judge the charms of submerged animals), he becomes at once a far more imposing creature. His hues are then even more vivid than those of the burnished swallow’s back; and his great black eyes gleam out from his lair with the watchful intelligence of the patient hunter.
Your lobster is an athlete of no small pretensions. He has three distinct modes of progression, and at least three sets of locomotive organs adapted to them. He walks or crawls on the sea bottom; he swims on the open; and he darts or jumps backward with his powerful tail muscles. Each of these modes requires at our hands a separate consideration.
The lobster’s legs, all told, are ten in number. But only eight of these are largely used for walking. The front pair, or big claws, have been specialised, as in the crab and most others of the higher crustaceans, into prehensile organs for catching and crushing the prey. Their use is obvious. Lobsters feed largely off mollusks of various sorts, and other hard-shelled marine animals; in order to be able to break or crush the shells of these, and so get at the softer flesh within, they have acquired such large and very muscular nippers or pincers. That is not all, however; not only have the two front legs been differentiated and specialised from the eight others in this manner, but also, by a rare exception to the symmetry of the body, the right claw has been specialised from the left, each being intended to perform a distinct function. One is a scissors; the other is a mill: one is a cutter; the other is a cracker. As a rule the right claw is the slenderer and longer; it has tooth-like projections or serrated edges on its two nipping faces, and it is rather adapted for biting and severing than for crushing or grinding. The left claw, on the other hand, is usually thicker, heavier, and rounder; its muscles are more powerful; and in place of sharp teeth it has blunt tubercles or hammers of different sizes; it acts, in fact, more like a nut-cracker than like teeth or a saw; it is a smashing organ. Nevertheless you will find it interesting to observe, by noting the lobsters served to you at table, that this differentiation has hardly as yet become quite constant; for sometimes it is the right claw that displays the hammer-like nut-cracker type, and the left that acts as nipper and biter; while sometimes no difference occurs at all, both claws alike being sharp-toothed or blunt-hammered in the same specimen.
Behind these two specialised forelegs or claws, which are really connected with the mouth and the capture of food rather than with the process of locomotion, come the eight true legs, employed in walking. On shore, indeed, or as you see the lobster lie on the smooth flat slab of a fishmonger’s shop, these legs are truly but feeble members. At home in the salt water, however, for which, of course, they are primarily adapted, they present a very different appearance. The buoyant medium supports and floats the heavy body and claws, and the animal moves along on the tips of his eight feet with a peculiarly graceful gliding motion. He hardly walks: he seems rather to slip through the yielding water. His nimbleness under such circum­stances surprises those who think of him only as a weighty and armour-clad creature, forgetting that in his own atmosphere (if I may venture on the phrase) he is buoyed and upheld by the sea that surrounds him on every side. When walking on the bottom in this way, in search of prey, he extends his big front claws obliquely before him, so as to offer the least possible resistance to the mass of water; six of his legs he uses as true legs alone; the last pair of all he employs rather as picks or stilts, if I may use such a metaphor, pushing them firmly into the sand or pebbles on the bottom, and steadying by their aid his forward motion.
The second set of locomotive organs are the swimmerets, or fin-like appendages under the animal’s tail, each of which acts as an oar or paddle. They consist of a short stalk or handle, fitted with two flat wide blades. When the lobster walks on the bottom, he extends his tail unfolded behind him, and gently waves these swimmerets like a fish’s fins to assist and guide his forward movement. They thus play the part at once of oar and rudder, though the latter function is still more efficiently per­formed by the expanded organs which terminate the tail. But the lobster can also use the swimmerets to swim with alone, independently of the crawling or creeping legs; and though this motion is but slow and slight it has a peculiarly graceful and mysterious appearance. A swimming lobster seems to glide through space with fairy elegance. As a rule, however, the lobster sticks to the bottom, and only swims obliquely downward for very short distances from its home in the rock to the sands beneath it. Nor is this the only function of the swimmerets. Nature, we all know, is economical of organs; and therefore we need not be surprised to learn that in the female lobster the swimmerets are further utilised to serve as supports for the eggs, or ‘berry,’ in a way which will arrest our attention a little later.
And now we come to the third and by far the most powerful organ of locomotion in the lobster, the large and very muscular tail. Strange to say, however, this organ acts in the opposite direction from the other two; by its aid the animal is able to spring rapidly, not forward, but backward. Why backward? Well, the tail is not used as an ordinary means of locomotion at all, but is reserved for purposes of sudden retreat and defensive action. As the lobster walks about over the hunting-grounds near his lair (for of course he has preserves of his own around his estate), he keeps his long antennae, or feelers, constantly waving up and down before him, so as to give him warning of the approach of a dainty morsel or a stronger enemy. On these rather than on his imperfect stalked eyes he seems to rely most for information and for danger signals. If the offending object be not big enough or active enough to frighten him, he stands up menacingly on his walking legs and puts himself in the exact attitude of a boxer. One large claw he holds for defence in front of his head; with the other he strikes out against the hostile object, and strives to crush or kill it. Fishermen sometimes draw lobsters from their holes by presenting them in this way with a blade of an oar; the un­suspicious crustacean seizes it with his claw and refuses to let go, sometimes even permitting himself through pure obstinacy to be drawn out of the water. But when the enemy is one of whom the lobster is afraid he retreats precipitately by bending his big tail with a spasmodic jerk, which drives him backwards through the water at the rate of twenty-five feet in a second. In clear water you can see them dart past like lightning when disturbed or terrified. In this peculiar backward jump the animal is also largely aided by the fan-shaped, rudder-like organs at the end of the tail.
As a rule, when thus alarmed, the lobster darts away backward into deeper water, where he is not likely to hurt himself by knocking against hard foreign bodies. But he has also no small delicacy of adjustment in this matter of jumping, and if near his own home—for every lobster has a recognised house of his own in some cranny of the rocks—he will fling himself into it backward with an accuracy of aim like that of a swallow or sand martin swooping down upon its nest from a considerable distance. The tail is thus an organ of defensive retreat, and its large size is the index of its use to its possessor.
It may be interesting to the culinary naturalist to observe in passing that this distribution of the locomotive organs is mainly answerable for the varieties and disposition in the flesh of the lobster. The large crushing claws, constantly used in feeding, have firm but not hard or stringy flesh, and are much more digestible than the other portions. The small walking legs, having relatively little work to do, are supplied with smaller muscles, dis­tributed in an intricate and peculiar network of thin shelly material. But the big and powerful tail, employed for the violent act of leaping, and constantly exerted in the state of nature, has correspondingly hard and strong muscles, which form the mass of the edible portion, but are relatively indigestible through their closeness and toughness. In the crab, on the other hand, which merely crawls, we eat mainly the claws and the lesser leg-muscles.
Lobsters are essentially nocturnal animals, lurking for the most part in their holes during the day, and coming out to feed on the sands by night. It is for this reason, no doubt, that they depend so little upon their imperfect eyes, all the more so as they inhabit a depth of water where light becomes of very slight importance. On the other hand, it is probable that the antennae end in organs of smell of a delicately discriminative sort, and that by their aid the lobster knows friend from foe and food-stuff from enemy.
Our crustacean not only roams the sea bottom in search of food, but also digs and burrows in the sand and mud, like a maritime mole, in pursuit of shell-fish. These he catches and crushes with his hammer-like claw, extracting the soft parts to eat at leisure. But he is also an angler after fish, which form, perhaps, the chief portion of his diet; and he preys to a great extent upon his cousins the crabs, whose thinner shells and more exposed habits make them an easy booty. In aquariums lobsters also clearly display cannibal habits; if one lobster loses a claw his neighbours unanimously turn and rend him. That this evil habit exists still more abundantly in the native state we have unfortunately more than ample evidence, for in the stomachs of old specimens the shells of their juniors and even of hen lobsters have been frequently recognised. Such ungallant conduct almost seems to justify the extreme sentence of boiling alive, to which lobsters caught by man are usually subjected. As to the question whether their prey is living or dead, lobsters are far from particular. All is fish that comes to their net. They rank, in fact, among the chief scavengers of the sea, and though they habitually catch and eat living animals they do not despise dead and decaying specimens. They are at once the tigers and the hyenas of their world; they double the parts of the eagle and the vulture.
The early history of the lobster is full of interest. He undergoes in his infancy a series of metamorphoses at least as curious, as varied, and as instructive as those of the frog and the butterfly. The eggs, which are deep semi-transparent green in the living animal, not bright red, as we see them when boiled, are laid in early autumn. But the careful mother does not turn her offspring loose at once on a cold and unfeeling world; she fastens the ‘berry’ sedulously to her own swimmerets, by means of gummy adhesive threads, and carries it about on her journeys for several months thus closely attached to her own person. Meanwhile the motion of the swimmerets assists in aerating the eggs and promoting maturation. By June or July of the succeeding summer the young fry are hatched out, being rather less than half an inch long at the moment of escape from the leathery egg-shell. The hen lobster lays from 2,000 to 12,000 of these little round eggs; but out of that large family only about 1,000 usually hatch out, while not more than three or four of the whole brood in all probability ever arrive at maturity. The rest are killed by natural causes in infancy, or devoured by their own kind and other enemies.
And here we get a measure of the ferocious cannibalism which, I grieve to say, prevails among our subjects. Young crayfish, first cousins of the lobsters, have hooked forceps claws, as Huxley pointed out, by means of which they cling, after hatching, in little colonies to their mother’s swimmerets. Thus the maternal crayfish crawls about her native stream, like the kangaroo, carrying her young ones with her; while the baby crayfish, good brothers and sisters, derive shelter and food from this motherly solicitude. But the bloodthirsty young lobsters, as soon as hatched, instantly disperse themselves with a sort of natural repulsion, after the curious fashion of a brood of baby spiders, and for the selfsame reason. As Dr. Herrick, the author of a learned and exhaustive work on the American lobster (a species which differs but little from our own), rightly remarks, ‘a swarming or gregarious habit would be fatal to this creature, on account of its inborn pugnacity and cannibalism.’ The family disperses to avoid being eaten by its unnatural brothers.
Our young lobster, once more, emerges from the egg not lobster-like in form, but as a lobster tadpole or larva. In this its earlier avatar it is an active, free-swimming pelagic creature, not unlike, in general look at a first rough glance, to the familiar mosquito larva—with which, of course, I need hardly say it has no real affinity. Its early history, which has only of late been traced in detail, is far too varied and minute for popular appre­hension; it must suffice to say that the baby lobster swims openly on the surface of the water, and undergoes several moults, each accompanied by marked changes of structure and appearance, before attaining its adult form and its final walking and leaping habits. In the earliest stage our larva is quite transparent, about half an inch long, and possessed of grotesquely big eyes, such as befit a free-swimming, surface-haunting animal; at this level it nearly approaches a much lower and presumably ancestral form of crustacean development. Very young lobsters subsist mainly upon killing and eating one another, which is the survival of the fittest reduced to its simplest and most naked terms. The family utilises its less active members for the development of the more powerful. At each moult, however, the animal grows more and more lobster-like in shape, while recapitulating, as it seems, the various stages in the evolution of its kind from a very primitive crustacean progenitor. During all this time our larvae are diurnal not nocturnal in habit; they therefore depend more largely upon sight than upon smell as the leader among the senses.
Even when the young lobster reaches the full lobster form, however, he is still far from adult; he goes on growing for many months, or even years. But he now quits the surface and takes entirely to a nocturnal life on the ill-lighted sea bottom, for which his existing locomotive organs and his adult senses are specially adapted. Still he continues to moult or cast his outer shell— many times yearly in the very young, once a year in the adult, less frequently still in old and thoroughly hardened specimens. This moulting is, of course, necessitated by the very conditions of growth themselves, for an animal encased in such a coat of solid armour must either not grow at all or else cast off its mail and renew it periodically. Naturally the lobster follows the last of these two plans; his moulting is a result and accompaniment of growth.
Odd as it may sound to say so, the animal grows before, not after, he casts his old hard shell—that is to say, he makes new cells and tissues, which are not at once filled out, but which are intended to plim to their full dimensions as soon as he has got rid of his binding and confining external skeleton. When the critical moment at last arrives, a new soft shell grows entire within the older and harder one; and the animal then withdraws himself, leg by leg, claw by claw, and swimmeret by swimmeret, out of the enveloping coat of mail which covers him. The shedding of the old coat is complete and absolute; not a fragment remains; even the apparently internal hard portions are cast off with the rest, for the entire covering forms one continuous piece, the interior por­tions being really, so to speak, folds of the skin inserted inward. An entire new skeleton has already grown within the old one, but exceedingly soft and flexible in texture, and the body becomes so almost fluid or jelly-like (not in structure, but in power of compression and extension) that even the big claws are drawn out through the narrow apertures of the joints in a perfectly marvellous manner. After a longer or shorter period of muscular paroxysm, the soft lobster at last disengages itself entirely from the dead shell, and emerges upon the world a new and defenceless fleshy creature. The whole cast skeleton, unruptured in any part, but disengaged by lifting up the body-piece where it joins the tail, looks exactly like an entire dead lobster.
Immediately after the moult the apparent growth takes place with extraordinary rapidity. Recent investigators have shown that this rapid growth depends upon the absorption of water into the blood and tissues through the soft new shell. For at the moment when the lobster emerges from his old coat the new one is already fully formed in every part beneath it; the skeleton needs only hardening matter in order to solidify it into a complete suit of armour, like the old one, but larger. So far as its living matter is concerned the lobster is now really bigger than before; he requires just water to fill him out and lime to harden his newer and larger shell; but when these have done their respec­tive work he has completed his growth till the next moulting period. He thus grows, as it were, by fits and starts at measured intervals.
Moulting, however, is both dangerous and expensive. Many lobsters die naturally in the process; others are eaten up by unkindly neighbours of their own species or by foreign enemies during their defenceless convalescence. It is commonly said by fishermen and others that lobsters after moulting retire to their lairs, and pass through a period of complete inactivity till their shell has hardened. This idea, however, is probably due to the misconception that the new shell is formed after, not before, the shedding of the old one. As a matter of fact the soft lobster does really retire as far as possible from vulgar observation and too curious inquiry during his softest time; but he nevertheless ventures out by night to feed, a point rendered certain by the comparative frequency with which soft specimens are caught round the coasts in lobster pots. But the new shell hardens rather rapidly, partly because the lobster has providently laid by in readiness in his body a supply of lime in easily soluble forms, and partly because the neophyte swallows fragments of shells and other calcareous matter, as Dr. Herrick points out, which he dis­solves in his stomach and uses up in hardening the new coat of mail. Thus in a few days the fresh shell has acquired a leathery consistency, and by the end of six weeks it is as hard as the old one.
Closely connected with this habit of moulting is the still more peculiar power known as ‘recrescence’—the faculty of reproducing lost limbs and organs. Lobsters and crabs, as we have seen, are highly pugnacious and aggressive creatures, which fight to the death with one another and with alien enemies; but if seized by the nipper claws they seem instinctively to recognise, that further fighting is useless, and instead of continuing the hopeless battle they cast off the offending limb and retreat with­out it, thinking it better to lose one claw than life and freedom. Nature provides beforehand, in fact, a definite place where such sacrifices should be made, by making a break at the base of the leg; the ruptured surface hardly bleeds at all, while in a short time a new claw buds forth from the severed end and replaces the old one. The antennae and small legs also grow again when broken off by accidental injury.
This fact of recrescence, found also in lizards and some other animals, and common in plants, is of profound interest in philoso­phical biology, as Mr. Herbert Spencer was the first to point out; for it suggests the idea that the formative material or protoplasm in every organism has a natural tendency to reproduce in its entirety the native form of the original creature, much as crystals have a tendency to precipitate from their mother liquid in certain characteristic or specific shapes. When this ideal entire form is mutilated the common plasm rebuilds the broken part; and Mr. Spencer struck out the luminous idea that just in the same way the egg or germ tends to rebuild by its own internal energies the shape of such a body as that from which it was originally derived. The mystery of birth becomes thus to some extent a mere special case of the mystery of the rebuilding or recrescence of the body. Assimilated matter, once taken into the organism, has the power either of restoring that organism complete or of forming new organisms essentially similar. This is the most pregnant hint as to the true nature of heredity that has yet been thrown out by any biologist.
Only two other species of true lobster beside our own are ‘known to science’—the American and the Cape lobsters. They differ in petty details alone from the European form; the American kind is noticeable chiefly for the much larger size of its crushing claws, a fact which may have struck the prudent housewife in the course of opening and currying the tinned lobster of commerce. I apologise, however, for the obtrusion of such a fact in the present article, for I am prepared to admit that no crustacean is really at home when boiled and potted. I think the reason for this abnormal development of the crushing claws in the American species must probably be sought in the generally harder nature of the solid mollusks on which it feeds. Our English species seems to live mainly on true fish, soft crabs, and such relatively thin-shelled mollusks as mussels, razor fish, and cockle-like forms. But the American lobster, a great borrower after buried sand mollusks, makes a large part of his living out of the very hard clams and other solid-shelled mollusks of the western shore, exposed to the terrible roll of the Atlantic waves on the exposed coasts of Maine, Massachusetts, and Nova Scotia. He therefore needs larger and more powerful claws in order to crush these very tough food-stuffs. Huge heaps of clam shells are often observed at the end of the lobsters’ burrows in the West, as are the remains of our less pro­tected English shell-fish at the mouths of the holes frequented by our own species.
The so-called Norway lobster, occasionally taken on the British coast, is a much more distant cousin, belonging to a separate genus, Nephrops, with slenderer claws, well adapted for picking food out of crannies in rocks, and is distinguished by a somewhat more prawn-like and graceful aspect. As to the spiny lobster, or langouste, dignified by science with the imposing classical title of Palinurus, he is still less of a relation, more South European in type, and found in Britain only on our southern shores. He poses as a sort of sea hedgehog, being covered all over his body with projecting spines, and adapted rather for defence than defiance. His marked peculiarity lies in the fact that he has no crushing claws at all, being content with ten almost similar walking legs, the first pair of which scarcely differ in any way from the others. In this curious form we may probably recognise the modern representative of some primitive and less developed ancestor, little given to attacking hard food or enemies, and therefore unprovided with fighting or crushing members. In the more advanced lob­sters, on the other hand, the front claws have been progressively modified and specialised for this important function. The spiny coat of Palinurus points, no doubt, in the same direction. For animals which can fight, like the lion or the bull, do not generally need such passive protections; it is usually skulkers and belated relics, like the porcupine and the hedgehog, which have survived by acquiring these unwarlike armours.
The true lobsters are thus seen on the whole to be the princes and heads of crustacean nature. In a single word, they are a dominant family. Where they live they rule. Few enemies can tackle them; their most dangerous foes are those of their own household. Armed offensively with their mighty claws, armed defensively with their impenetrable carapace, they attack boldly, and fear or shrink from few hostile creatures. Yet they have the power, when alarmed, of beating a rapid and effective retreat with their muscular tails, or of leaving their claws, when necessary, behind them. They can either carry out a strategic movement to the rear into deeper water, or dart back with a bound to the safety of their rock shelter, where, with body protected and only the armoured head, spiked frontlet, and huge claws projecting, they present a terrific face to the most determined aggressor. No creature of their size is more formidable or better armed. They represent in our seas the highest result of natural selection in the crustacean line, perhaps even the most splendid development of the mailed soldier type now living on our planet. And when seen by the proper light in their native element they are as beautiful in hue and as graceful in movement as they are wonderful in shape and terrible in fighting.

Grant Allen.

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As an armed forces brat, we lived in Rockcliff (Ottawa), Namao (Edmonton), Southport (Portage La Prairie), Manitoba, and Dad retired to St. Margaret's Bay, NS.
Working with the Federal Govenment for 25 years, Canadian Hydrographic Service, mostly. Now married to Gail Kelly, with two grown children, Luke and Denyse. Retired to my woodlot at Stillwater Lake, NS, on the rainy days I study the life and work of A. Hyatt Verrill 1871-1954.