CRABS AND SHRIMPS. 183 



" 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, swimming 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 secure accuracy of result, one of the Crabs 



ZOEA OF SHORE-CRAB. 



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 wit- 

 nessing, beneath the microscope, the natural bursting and 

 escape of one precisely similar in form to those found so 

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

 that these grotesque-looking creatures are the young of 

 the Carcinus m<znas ; but how different they are from the 



