188 



GAMMARIDJ8. 



It may be that they are synonymous, but the very im- 

 perfect manner in which Say's genus is described, arising 

 from the want of fixed homological names for the several 

 parts of the animal, precludes us from expressing more 

 than a supposition of their identity. 



The habits of the only species of Sulcator appear to 

 differ from those of the only species of Lepidactylis de- 

 scribed, inasmuch as the former is very sluggish, and a 

 burrower, whereas the latter is stated by Say to be very 

 active, much resembling in its movements the water- 

 beetles of the genus Dytiscus. 



The accompanying vignette represents one of our fa- 

 vourite hunting-grounds, the Tor Rock in Oxwich Bay, 

 near which our specimens of this genus were taken. 



