10 



Spawning of 

 crabs. 



Crabs shedding 

 their shells. 



" appendage ; the feet are scarcely visible with the exception of the last 

 " two pairs, which are ciliated like those of a branchiopod, and formed 

 " for swimming. The tail is longer than the body, possesses no false feet, 

 " and the terminal joint is crescent-shaped and covered with long spines. 

 " The eyes are|very large, and a long beak projects from the lower surface of 

 " the head. 



" In a more advanced stage of growth the creature assumes a totally diffe- 

 " ernt shape, under which form it has been known to naturalists by the name 

 " of Megalopa. The eyes become pedunculated, the cephalothorax rounded, 

 " the tail flat, and provided with false feet, and the chele and ambulatory extre- 

 " mities well developed. 



" A subsequent moult gives it the appearance of a perfect crab, and then only 



does the abdomen become folded under the thorax and the normal form of 



the species recognisable." 



By the kindness of Mr. Henry Lee, F.L.S., I am enabled to give drawings of 

 the crab in its early stages of transformation. Fig. 1 {see Diagram No. 5) 3 repre- 

 sents the young crab just as he came out of the egg ; fig. 2 is the next form 

 which it assumes previously to its becoming a perfect crab. These early forms 

 of the Zoea crab are as unlike the parents as can possibly be conceived. The 

 specimen figures were hatched under Mr. Lee's personal observations as 

 Consulting Naturalist to the Brighton Aquarium. 



My own opinion agrees with that of Mr. Spence Bate, who says : — " The 

 " berries will be exposed in January and carried till May ; soon after that the 

 " berries are hatched, out .... In Mav the water is tinged with the young 

 " Zoea." 



But berried crabs with ova under the apron may be obtained in December 

 and January. Mr. Climo, of Polruan, stated : — " Once he had been fishing 

 " in October, and had left some crabs in a store pot till after Christmas ; in 

 " January every one was full of spawn. There were nine or ten crabs." 



Other evidence was given at various places to this effect : e. g. at Prawle : — 



"About December the she crabs are berried; they are berried in December, 

 " January, and February." 



Mr. Harvey, a London fishmonger, said, " The hen crabs would have the 

 berries under their tail in the beginning of December." 



It is the opinion of some that crabs spawn out at sea, i.e., that the young 

 are hatched out at sea. I am not of that opinion. The mistake, I think, has 

 arisen on the different interpretations of the word "spawning." This may 

 mean 1st. Carrying eggs. 2nd. The time when the young are hatched. My 

 belief is (as I have said before), that crabs spawn — in the sense of first 

 appearing " berried " — out at sea, but the real hatching out takes place in the 

 warm spring months near the shore. All young things require warmth and 

 food. The young salmon are born in the spring, absorb their umbilical bag, 

 and become active just at the time their insect food is most abundant. Most, 

 I may say all, sea-fish fry are found in the spring, and I am, therefore, led to 

 conclude that the young zoea come out of the eggs in the spring, when 

 there are three things present for their comfort and to assist their growth — 

 1, warmth; 2, quiet water ; 3, food. At that time both animal and vegetable 

 life are just bursting forth into existence, and the food minute enough for the 

 zoea to eat is at that time found in most abundance. In many parts of England 

 the smallest crabs are found in May and June. 



Young birds are born in the spring for the same reasons. If young crabs 

 were born out at sea in the winter time, the conditions would not be favourable 

 for them. My statement is further confirmed by the fact that the very small 

 crabs, the first real crab-like creature after the zoea state, are found on the 

 foreshore in the shallow warm water in the spring time. 



As the crab is encrusted with a hardened and inelastic shell, composed of 

 carbonate and phosphate of lime, and chytine, it is not able to grow like any 

 other creature; it therefore periodically sheds its shell. I have a very fine 

 specimen in my museum of a crab which I took myself at Heme Bay, where it 

 is locally called a Punger, in the actual process of shedding its shell. The 

 shell when about to be cast off is split along the underside of the body from the 

 mouth to the tail. This line of division, I find, is plainly marked in the shell 

 of a full-grown crab. 



It is not known how many times a year a crab sheds its shell. 



