INTRODUCTION. XXXVll 



In the account of the great crab, p. (32, I have stated 

 that the male lies in wait for the female previous to and 

 during her moult, and seizes her as soon as this is ac- 

 complished, whilst she is still weak and enfeebled by 

 the process; and I have so commonly seen the male 

 and female shore-crab (Carcinus Manas) in conjunction 

 when the latter is still soft, that there can be no doubt 

 that this is a general, although certainly not a constant 

 habit. 



A no less curious and interesting process than that 

 above described, is the voluntary casting of the limbs, 

 and the restoration of such as have been thus lost by the 

 animal's will, or by accident. Reaumur in this case also 

 was the first to make any correct and scientific researches 

 on the subject, and his statements, full of interest, will be 

 found in the earlier of the two memoirs already quoted. 

 My friend Mr. Couch has subsequently extended these 

 observations, which will be found embodied in my account 

 of the habits of the lobster at page 245. 



On this subject an interesting paper was read before 

 the Wernerian Society of Edinburgh by Mr. H. Goodsir, 

 in December, 1843 ; and to the details which I have given 

 in the place above mentioned, I would merely add a short 

 abstract of Mr. H. Goodsir's paper:* 



" It has long been known that the animals belonging to 

 this class have the power of reproducing parts of their 

 body which have been accidentally lost. If one of the more 

 distant phalanges of a limb be torn off, the animal has 

 the power of throwing the remaining part of the limb off' 

 altogether. This separation is found to take place always 

 at one spot only, near the basal extremity of the first 



* Annals of Nat. Hist. vol. xiii. p. 67. 



