CRABS AND SHRIMPS. 



183 



Having procured some specimens of the Shore-crab 

 laden with eggs just ready for shedding, he goes on to 

 say, " These were transferred to captivity, placed in 

 separate basins, and supplied with sea-water ; and in 

 about sixteen hours I had the gratification of finding 

 large numbers of the creatures alluded to above, swim- 

 ming about with all the activity of young life. There 

 could be but little doubt that these creatures were the 

 young of the captive Crabs. In order, however, to 



ZOEA OF SHOKE-CKAB. 



secure accuracy of result, one of the Crabs was removed 

 to another vessel, and supplied with filtered water, that 

 all insects might be removed ; but, in about an hour, the 

 same creatures were observed swimming about as before. 

 To render the matter, if possible, still more certain, some 

 of the ova were opened and the embryos extracted ; but 

 shortly afterwards I had the pleasure of witnessing, be- 

 neath the microscope, the natural bursting and escape 

 of one precisely similar in form to those found so 

 abundantly in the water. Thus, theD, there is no doubt 

 that these grotesque-looking creatures are the young of 

 the Cavchms memos; but how different they are from 



