CRABS AND SHRIMPS. 



18' 



a Megalopa ; and this latter became, after a short time, 

 a Crab, in which were all the characters that belong to 

 the order to which the parent belongs ; but not those of 

 the genus nor even of the family. Its form bore a close 

 resemblance to that of the Sargasso Crabs (Gra-psidcr) ; 

 for the shield, instead of being large and arched in front, 

 and narrowed behind, was nearly square, while the front 

 was (taking in the eyes) almost straight, the lateral 

 angles much advanced. 



THIRD STAGE OF SHOBE-CRAB. 



(Grapsoid.) 



This Crab, however, was still very minute : and many 

 sloughings were before it. In the course of these it was 

 destined gradually to attain, not only the dimensions of 

 its parents, but also their form. This, however, would be 

 matter of development rather than metamorphosis : the 

 lateral outlines of the shield would more and more ap- 

 proach each other behind, while the series of points that 

 now belonged to these lateral outlines would become 

 thrown into the front margin, which would by degrees 

 assume an arched form, as you may see in the figure of 

 the adult Crab. 



Though I cannot at this moment show you specimens 

 of the Carcinas in its earlier stages, yet I have here a 

 good number of the Zoeas of one of those intermediate 

 form s which are the connecting links between the Crabs 

 and Lobsters : I mean Galathea. The adult animal is 



