Tin: SQUALIDS.— THE LOBSTER. 



its body is crowded witli small, dark, reddish-brown 

 6|) jts on a pale reddish ground ; the spots being rather 

 larger and less numerous on the fins. It is a very 

 common species on the south coast of England, where 

 it feeds on small fish and Crustacea, lying in ambush to 

 surprise its prey. 



The Picked Dog-fish (Spinax acwHhias), a gpecies 

 exceedingly common on the Kent and Susses coasts, 

 where it is popularly known as the Bone Dog, is also 

 frequently met with on the west and north-east, and in 

 the shallow waters of the Western Islands. It is dis- 

 tinguished from other species of its genus by the single 

 spine placed in front of each of its two dorsal fins. 

 According to Mr. Couch, they are sometimes found 

 in incalculable numbers, so as greatly to obstruct and 

 annoy the fishermen, whose hooks they cut from the 

 lines in rapid succession. 



The Picked Dog-fish curves itself into the form of a 

 bow for tlie purpose of using its spines, and by a sudden 

 motion causes them to spring asunder in opposite 

 directions ; and so accurately is this movement efl'ected, 

 that if a finger be placed on its head, it will strike it 

 without lacerating its own skin. Its usual length is 

 about twenty inches; the upper part of its head and 

 body are of a slaty grey colour ; the under parts wear 

 a yellowish tint. 



The Black-mouthed Dog-fish, so called from the 

 colour of the interior of its mouth, is a common species 

 in the Mediterranean. Its average length is from two 

 feet to two feet six inches ; its colour on the head and 

 upper part of the body is a light brown ; aud along 

 each side run two rows of ocellated spots. 



It has been suggested that of all marine animals the 

 IIammerheadeu Shark {Zijgana malleus) is pro- 

 babl}' the most deformed, though it must be remembered 

 that we do not as yet know all the monstrous shapes 

 and " chimoeras dire " which the dark unfathomed caves 

 of ocean may contain. Certain it is, however, that 

 its aspect is calculated to disgust, aud even terrify, the 

 spectator. It resembles the ordinary shark in the sub- 

 cylindrical conformation of its body, but is distinguished 

 from it by the peculiar shape of its head, which is 

 ddatcd on either side so as to resemble a double-headed 

 hammer. The eyes, which are very large, are placed 

 at the extremity of these lateral prolongations ; they 

 are grey, prominent, and with a gold-coloured iris. 

 When the animal is irritated, the irides seem to light 

 up with a sudden flame, much to the horror, it is said, 

 of the fishermen who beliold them. 



The mouth, which is semi-circular, is placed beneath 

 the head, and near to the junction of the trunk. It is 

 furnished in each jaw with three or four rows of large 

 tcetli pointed and barbed on both sides. 



The Hammerhead is a native of the Mediterranean 

 and the Indian seas, and is scarcely less formidable 

 for voracity and fierceness than the ordinary shark, 

 attacking any ]ierson who may he unfortunately bathr 

 iiig in its vicinity. In our European seas the most 

 common species is long and slender in the body, which 

 is grey, with a blackish- coloured head. It usually 

 attains the length of eleven or twelve feet, and the 

 weight of four to five hundred pounds. Its voracious 

 fury often brings it round vessels even in the road- 



steads, and close in upon the coast. It is frequently 

 observed about the shores of the South Sea Islands, 

 those — 



'' Summer-isles of Eden, lying in dark purple spheres of sea,^ 



and jiarticularly in the bright blue waters of Otaheite ; 

 but the natives, confident in their surprising dexterity 

 as swimmers, and their consequent ahility to escape its 

 jaws, appear to hold it in very little terror. Every- 

 where, however, it is equally distinguished by its lust 

 of blood, its violent fury, its curiously characteristic con- 

 formatioir, and its hideousness of aspect, which stamps 

 itself on the memory of every beholder. Naturalists 

 do not suggest any particular function discharged by 

 its eingularly-shaped head, which seems to be simply 

 a specific distinction. 



THE LOBSTER. 



The manner in which the female lobster relieves 

 herself of her young is very curious. Whether she 

 bends or stands erect, she is still able to hold her 

 burden obscurely or to expose it to the light. Coste 

 asserts that the eggs are sometimes left immovable, or 

 simply submerged ; at others, they are subjected to 

 frequent washings and gentle oscillations of the falsa 

 claw which shelters them, from right to left. 



The eggs, when first exuded from the ovary, are 

 very small ; but they seem to increase during the time 

 they are borne about under the tail, and attain the 

 size of small shot before they are intrusted to the 

 water. The evolution of the germ continues for six 

 mouths. The female, at the moment of extrusion, pro- 

 jects the tail, and communicates to the eggs an oscil- 

 lating motion, so as to destroy the shell and disperse 

 the larv.ne. In the course of two or tliree days she 

 delivers herself of her entire burden. As the young 

 lie inclosed within the membraue of the egg, says 

 Couch, the claws are folded on each other, and the 

 tail is flexed on them as far as the margin of the shield. 

 The dorsal spine is bent backwards, and lies in close 

 contact with the dorsal shield ; for the young is quite 

 soft when it emerges from the egg, but is rapidly indu- 

 rated and solidified by the deposition of calcareous 

 matter on what may be called its skiu. 



No sooner are they born than tlie youug Crusta- 

 ceans abandon their mother, and ascend to the surface 

 of the water in order to gain the open sea. 



Theie they swim with a constant circular motion, 

 but for no very protracted period. After their fourth 

 moult, or sloughing, which occurs between the thirtieth 

 and fortieth days of their yoimg existence, they lose 

 their temporary organs of natation, aud unable to main- 

 tain themselves any longer in the ujiper waters, descend 

 to the bottom, thenceforth to assume the ordinary habits 

 of their kind. As they increase in size Ihcy draw nearer 

 to the shore, which they had previously abandoned, and 

 return to the localities inhabited by the parent Crustacea. 



In form the larva difl'ers so largely from the adult 

 that it would be difiicult, except on the strongest evi- 

 dence, to decide the particular species to which it 



