162 



M A Y. 



The Gyrinus villosus, one of the rarest spe- 

 cies of this genus, inhabits the weedy margins 

 of streams. It is supposed by some to differ 

 from its congeners in not being gregarious, but 

 of this I have some doubts, as it has once in 

 this neighbourhood been taken abundantly, 

 and to all appearance is as fond of collecting 

 together as the natator, although not so com- 

 mon or so frequently observed. The gentle- 



