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The following evidence was given us. Mr. Matthias Dunn thinks '* crabs 

 " shoot their shells at least once a year, and as often as they fill up. They 

 " must cast their shells more than once in 1(> months to grow from 4 to 

 " 8 inches across." Mr. John George, of Sennen, thinks, " crabs shoot their 

 " shells once a year. Has found them every year in a certain hole with their 

 " shells off in March and April." Mr. Laughrin, Polperro, stated "that large 

 " crabs shed their shell twice a year; small ones every four or five months." 



Other witnesses informed us that " a crab of 4 inches would shed his shell 

 " three times before he reached 8 inches." " Crabs are casting their shells 

 " between end of August and end of November." "A crab of 44 inches is 

 " about three years old." 



When a crab sheds his shell he sheds every part, not only of his external 

 covering, but also of the skin covering his internal viscera, even the horny 

 casings of his lung tufts. He also sheds the coating of his eye, and even the 

 external covering of his large pincher-like teeth. The coat and teeth of the 

 stomach are, I think, also shed, but I have not specimens to show this. When 

 a crab sheds his shell he increases considerably in size. In the appendix will 

 be seen a diagram showing the rapid increase in size at each growth! This 

 remarkable specimen was presented to me by Mr. Sandford of Cromer. The 

 crab had cast its shell in the crab pot, so that the empty shell and the crab 

 itself were luckily quite perfect. The empty shell measures across three inches 

 and seven eighths. The crab which came out of the shell measures no less 

 than five inches, namely one inch and one eighth larger than it was a few 

 minutes previously. I have ascertained for a fact that a crab is enabled to 

 draw out his claws through the narrow opening of the point where the claw 

 joins the body by the curious fact that the shell splits, just at this point. The 

 shell of the lobster also cracks at this point. (See specimen in my museum.) 



When at Dunbar, Mr. Hutchinson was good enough to give me a live Lobster shedding 

 lobster which had just cast its shell in a store-box ; the length of the lobster its slie11 ' 

 shell was 7 inches, and the length of the new lobster was 8 inches. Mr. 

 Hutchinson gives as evidence : — " It would be beneficial to everbody to return 

 " lobsters to the sea under 4| inches in the barrel ; a lobster measuring 4 inches 

 " to-day is worth 6d. ; each time it casts its shell it grows half an inch, so 

 " that very soon it would be worth double the money. A lobster grows half an 

 " inch in the barrel when it has shed its shell once." 



It is probable that when crabs arrive at an adult age, they will not shoot A £e ot crabs, 

 their shell. The evidence 1 have of this is a male crab from the North Sea, 

 measuring 6f inches across the back. Upon its back are two oysters. These 

 oysters have adapted themselves to the contour of the crab's back; they 

 measure respectively in the widest diameter about 3 inches. This individual 

 crab had not, therefore, shed its shell for three years. I have also another crab 

 which has one oyster attached to it. This crab (a female) is 7h inches across 

 the back. This oyster shell measures 3 inches across. To both these specimens 

 there are also large barnacles attached. I have also another specimen, presented 

 by Mr. J. Wiseman, of a crab on which six oysters are fixed ; the upper surface 

 of the crab is almost concealed by the oysters. This crab must have been in the 

 middle of a heavy fall of oyster spat. I have also two specimens of the common 

 spider orab of small size. On the back of one are attached no less than 10 

 mussels, which I conclude are two years old ; the other crab has, attached to 

 the lower surface of the claw, an oyster of about four months old, two other 

 small oysters are attached to the lower surface of the crawling legs. 



Oysters do not very often attach themselves to lobsters. There is, however, 

 a splendid specimen in the British Museum to which 20 oysters are attached. 

 I calculate this lobster had not shed its shell for four or five years. 



It is, however, to be observed that the crow, anomia, or saddleback oysters, 

 seem to be especially fond of adhering to the shells of lobsters. I do not know 

 why this should be : the crow oysters only come from warm water ; when, there- 

 fore, crows are found upon lobsters, it is quite certain that they inhabited places 

 where the temperature was somewhat warm. 



Not only do crabs cast their shells, but they not unfrequently, from some 

 cause or other, throw off their claws, and, strange to say, and it is interesting to 

 know, that they will grow again. I have a specimen of a crab whose larger claw 

 measures 12| inches long, and / inches in circumference at the largest part, while 



