318 



MUSEUM OF ANIMATED NATURE. 



[Lobsters; Shrimps. 



SECTION MACRURA. 



(Decapod Crusf aceans with the abdominal segments 

 well developed, and of which we may regard the 

 lobster as the type.) 



The genus of this section to which we shall turn, 

 and ti) which the last genera of the Aiiomura appear 

 in some respects to approximate, is one termed iMe- 

 galopa by Dr. Leach. It contains a few small spe- 

 cies remarkable for the comparative volume of the 

 eyes, which are set on short peduncles. The abdo- 

 men is narrow and extended, with seven segments ; 

 false feet four pairs. The Megalopa mutica (Kig. 

 3208) is found at the mouth of the Loire ; it is of a 

 brown colour, a is the species magnified ; b, inter- 

 nal antennae ; c, external antennse ; d, the animal of 

 the natural size. 



We may now pass to the genus Astacus, which 

 contains the common lobster, Astacus marinus, and 

 the River crayfish, Astacus fluviatilis, &c. Fig. 3209 

 represents the common lobster. We shall not at- 

 tempt to enter into a detailed account of the form 

 and structure of this well known species, so cele- 

 brated for its excellence as an article of diet, and 

 for the change of colour it undergoes in boiling. 

 This change, it may be remembered, served Butler 

 in his ' Huilibras ' for one of his humorous similes : — 



" Now, like a lobster boiled, the morn 

 From black to red began to turn." 



It is owing to the action of water at 212° Fahr. 

 upon the bluish-black pigment secreted by the 

 corium, and ditJ'used through the substance of the 

 tegumentary skeleton or armour, which it also se- 

 cretes. Alcohol, xther, and the acids also produce 

 the same effect. 



The lobster is found in abundance in clear water, 

 among submerged rocks, along various parts of our 

 coasts, and is captured nearly in the same manner as 

 the crab. It is not only from our own shores that 

 the markets are supplied with this delicacy ; thou- 

 sands are brought over from Norway, in a living 

 state ; five or six vessels in fact are constantly ply- 

 ing between the Thames and Norway, for this pur- 

 pose alone. On entering the river, the lobsters are 

 deposited in large wooden cases, properly perforated, 

 and secured in a creek called Hole Haven, on the 

 Essex side of the Thames, near the upper part of the 

 Sea Reach, whence they are transmitted to Billings- 

 gate according to the demand. Great numbers are 

 also brought from Scotland. The consumption of 

 lobsters in England is almost incalculable ; but the 

 vast destruction made is counterbalanced by an ac- 

 cording increase. By a wise provision the mainte- 

 nance of the species is fully secured, so great is its 

 fecundity. Dr. Basfen says that he counted twelve 

 thousand four hundred and forty-four eggs under 

 the tail of one female lobster; and that this number 

 was not the total amount. 



One of the best narratives extant of the habits 

 of the lobster is to be found in a letter from Mr. 

 Travis, of Scarborough, to Mr. Pennant, dated the 

 Klh ofOctober, 1768. We select from it the fol- 

 lowing extracts : — 



" We have vast numbers of fine lobsters on the 

 rocks near our coast. The large ones are in general 

 in their best season from the middle of October till 

 the beginning of May. Many of the small ones, 

 and some few of the larger sorts, are good all the 

 summer. If they be four inches and a half long, or 

 upwards, from the tip of the head to the end of the 

 back shell, they are called sizeable lobsters. If 

 only four inches, they are esteemed half-size, and 

 when sold, two of them are reckoned for one of size. 

 If ihey be under four inches, they are called pawks, 

 and are not saleable to the carriers, though in reality 

 they are in the summer months superior to the large 

 ones in goodness. The pincers of one of the lob- 

 ster's large claws are furnished with knobs, and those 

 of the other claw are always serrated. With the 

 former it keeps firm hold of the stalks of submarine 

 plants, and with the latter it cuts and minces its 

 food very dexterously. The knobbed, or numb 

 claw, as the fishermen call it, is sometimes on the 

 right and sometimes on the left, indifferently. It is 

 more dangerous to be seized by them with the cut- 

 ting claw than the other ; but, in either case, the 

 quickest way to get disengaged from the creature is 

 to pluck off its claw. It seems peculiar to the lob- 

 ster and crab, when their claws are pulled off, that 

 they will grow again, but never so large as at first. 



" The female or hen lobster does not cast her 

 shell the same year that she deposits her ova, or, in 

 the common phrase, is in berry. When the ova first 

 appear under her tail, they are very small and ex- 

 tremely black ; but they become, in succession, 

 almost as large as ripe elder-berries before they are 

 deposited, and turn of a dark brown colour, espe- 

 cially towards the end of the time of her depositing 

 them. They continue full and depositing the ova 

 in constant succession, as long as any of that black 

 substance can be found in their body, which, when 

 boiled, turns of a beautiful red colour, and is called 



their coral. Hen lobsters are found in berry at all 

 times of the year, but chiefly in winter. It is a 

 common mistake that a berried hen is always in 

 perfection for the table. When her berries appear 

 large and brownish, she will always be found ex- 

 hausted, watery, and poor. Though the ova are cast 

 at all times of the year, they seem only to come to 

 life during the warm summer muntlis of July and 

 August. Great numbers of them may then be found, 

 under the appearance of tadpoles, swimming about 

 the little pools left by the tides among the rocks, 

 and many also under their proper form,S-om half an 

 inch to four inches in length. 



"In casting their shells, it is hard to conceive 

 how the lobster is able to draw the fish of their 

 large claws out, leaving the shells entire and attached 

 to the shell of their body ; in which state they are 

 constantly found. The fishermen say the lobster 

 pines before casting, till the fish in its large claw is 

 no thicker than the quill of a goose, which enables 

 it to draw its parts through the joints and narrow 

 passage near the trunk. - The new shell is quite 

 membranous at first, but hardens by degrees. 

 Lobsters only grow in size while their shells are in 

 their soft state. They are chosen for the table by 

 their being heavy in proportion to their size, and 

 by the hardness of their shells on their sides, which, 

 when in perfection, will not yield to moderate pres- 

 sure. Barnacles and other small shell-fish adhering 

 to them are esteemed certain marks of superior 

 goodness. Cock lobsters are in general better than 

 the hens in winter ; they are distinguished by the 

 narrowness of their tails, and by their having a 

 strong spine upon the centre of each of the trans- 

 verse processes beneath the tail which support the 

 four middle plates of their tails. The fish of a lob- 1 

 ster's claw is more tender, delicate, and easy of 

 digestion than that of the tail. Lobsters are not 

 taken here in pots, as is usual where the water is 

 deeper and more still than it is upon our coast. Our 

 fishermen use a bag-net fixed to an iron hoop, about 

 two feet in diameter, and suspended by three lines 

 like a scale. The bait is commonly tish-guts tied 

 to the bottom and middle of the net. They can 

 take none in the daytime, except when the water is 

 thick and opaque : they are commonly caught in 

 the night ; but even then it is not possible to take 

 any when the sea has that luminous appearance 

 wliich is supposed to proceed from the Nereis noc- 

 tiluca. In summer the lobsters are found near the 

 shore, and thence to about six fathoms' depth of 

 water ; in winter, they are seldom taken in Jess than 

 twelve or fifteen fathoms. They are much more 

 active and alert in warm weather than in cold. In 

 the water they can run nimbly upon their legs or 

 small claws, and, if alarmed, can spring tail fore- 

 most to a surprising distance as svvilt as a bird can 

 fly. The fishermen can see them pass about thirty 

 feet, and, by the swiftness of their motion, suppose 

 they may go much farther. Athenaeus remarks this 

 circumstance, and says that the incurvated lobsters 

 will spring with the activity of dulphins. Their 

 eyes are raised upon moveable bases, which enables 

 them to see readily every way. Wlien frightened, 

 they will spring from a considerable distance to 

 their hold in the rocks ; and what is not less sur- 

 prising than true, will throw themselves info their 

 hold in that manner through an entrance barely 

 sufficient for their body to pass, as is frequently 

 seen by the people who endeavour to take them at 

 Filey Bridge. In frosty weather, if any happen to 

 be found near the shore, they are quite torpid and 

 benumbed." 



The lobster was known to the ancients and is 

 probably the airTOKoe of the Greeks. 



The River crayfish (Astacus fluviatilis) is a 

 native of the rivers and streams of our island and 

 the adjacent continent, especially where the bed is 

 rocky and stony. 



Passing from the lobsters we may next turn to 

 those crustaceans known as shrimps and prawns. 

 And here we may remark that under the term 

 .shrimp are sold at Billingsgate and other markets 

 two very distinct species, belonging indeed to dif- 

 ferent genera; one the common shrimp (Crangon 

 vulgaris), the other allied to the prawn, and olten 

 termed the white or Medway shrimp (Palemon 

 squilla). We shall first notice the Crangonians, or 

 true shrimps, in which the anterior limbs are sub- 

 cheliform, terminating in a hooked moveable claw, 

 to which is opposed a fixed spine on the penulti- 

 mate joint. In Crangon the carapace is depressed, 

 and presents only the rudiment of a rostrum ; the 

 eyes are short, large, and free : the antennse are 

 inserted nearly on the same transversal line. The 

 locomotive limbs are slender and long ; the two 

 last the longest and shortest. The details of Cran- 

 gon are given at Fig. 3210, in which the forms of 

 the antennae and limbs are well delineated: a, the 

 mandible. 



It has been proposed to separate from Crangon 

 a genus under the name of Egeon (Risso), but on 

 slight grounds, deemed insufiicient by Desmarest : 



I 



the second pair of limbs are very short and didac- 

 tylous, and the last visible joint of the outer jaw- 

 feet enlarged. To this genus, or rather sub genus, 

 belong the Egeon loricatus (Cancer loricatusl of 

 the European seas. It is represented at Fig. 3211. 

 Fig. 3212 represents the common shrimp CCiangon 

 vulgaris) : a, one of the claws. 



This species, the Crevette or Chrevette and Cardon 

 of the French, is too well known to need a deseiip- 

 fion. It is taken on the flat sandy shores of our 

 island, and of the adjacent continent, often by boys 

 and women, who wade up to their knees or liisher, 

 pushing a sort of dredge net at the end of a long 

 pole before them ; a more wholesale way of col- 

 lecting them is by means of sweep nets, dragged over 

 the fishing-ground hymen in boats. The degree of 

 success is variable, but sometimes immense numbers 

 are taken. Paley in his ' Natural Theology ' relates 

 a circumstance which will give some idea of the 

 shoals of these animals which wander through the sea. 

 " Walking,'' he says, " by the seaside, in a calm even- 

 ing, upon a sandy shore and with an ebbing tide, I 

 have frequently remarked the appearance of a dark 

 cloud, or rather very thick mist, hanging over the 

 edge of the water, to the height perhaps of half a 

 yard, stretching along the coast as far as the eye 

 could reach, and always retiring with the water. 

 When this cloud came to be examined, it proved 

 to be nothing else than so much space filled with 

 young shrimps in the act of bounding into the air 

 from the shallow margin of the water or the wet 

 sand." Any attempt to calculate the numbers 

 composing an extensive cloud of shrimps must be 

 overwhelming. 



By way of pictorial illustration we give at Fi^. 

 3213 the spirited figure of a young shrimp-catcher 

 examining his net, the scion of a bold race, that 

 " weel the boatie row, to win the bairn's bread." 



Another tribe of shrimps, of stouter form than 

 the preceding, are termed Alpheans j the genus 

 Alpheus being the type. 



To this tribe belongs a singular species, the only 

 known example of the genus Atya, in which the two 

 anterior limbs are equal, with the penultimate joint 

 short, the last joint divided. 



The Atya scabra. Leach, Fig. 3214, is a native of 

 the seas of North America. 



The Palemonians, Les Salicoques of the French, 

 constitute the next tribe of shrimps. The carapace 

 is armed with a great sabre-like rostrum, nearly 

 always serrated above. All the limbs are slender; 

 the two first pairs are generally didactylous, the 

 three last never so. The genus Palemon, of which 

 the prawn and the white shrimp are examples, has 

 the lamellar palp which covers the base of the 

 antennae, large, oval, and rounded, ciliated at the 

 endj and armed with a spine at its external border. 

 The internal antennae send off one short and two 

 long multiartilate filaments ; the external antennae 

 one long filament. The abdomen is large, with 

 ample oar-like false feet. The seas of India pro- 

 duce species of this genus of extraordinary size, as 

 do also those of the Antilles. Those found in our 

 seas are moderate or small. They swim well, and 

 the shoal on the appearance of an enemy scatters 

 rapidly in all directions. 



The Prawn, Palemon serratus. Fig. 3215, is cele- 

 brated as a great delicacy: its colour is grevish, 

 freckled with red and brown ; when boiled it' be- 

 comes of a clear flesh red. The white shrimp, Pale- 

 mon squilla, is an allied species of much smaller 

 size, and there is a third species on our coasts, 

 Palemon varians, which is still more diminutive. 



The prawn is much infested by a minute parasitic 

 crustacean (Bopyrus Crangorum), which inserts 

 itself into the branchial chambei's and adheres to the 

 branchiae. 



Another tribe comprehends several genera, as 

 Penaeus, Stenopus, Euphemia, &c., in which the 

 abdomen is extremely elongated ; and the limbs 

 often carry a pali)ilorm appendage at their base 

 more or less developed ; and vary much in their 

 conformation. But we must pass from them to a 

 remarkable tribe of crustaceans, called Scyilarians, 

 to be distinguished at once by the singular conforma- 

 tion of the antennae. 



The carapace is very wide, and presents anteriorly 

 a horizontal prolongation advancing between the 

 base of the external antennae, and covering the 

 insertion of the first pair. The eyes arc placed in 

 well formed orbits, and are remote from each 

 other. The first pair of antennae present nothing 

 very remarkable ; tliey are rather short, and bifid 

 at their apex. The external antennae are like wide 

 foliaceous expansions. The abdomen is wide, and 

 terminates in a great fan-shaped fin. The jaw-feet 

 are moderate. 



In the first genus, Scyllanis, the carapace is 

 longer than wide, the lateral borders are parallel, 

 the orbits lateral; the abdomen stout. Fig. 3216 

 represents one of the jaw-feet. 



Fig. 3217 is the Scyllarus aequinoctialis, a large 

 species, measuring a loot in length, found in the 



