ENTOMOLOGICAL CABINET. 



GYR1NUS VILLOSUS. Illiger. 



Gyrinus Modeeri. Marsham. 



Scarce Water-flea. 



Upper part black and shining : head nearly trian- 

 gular, projecting and slightly reflexed, with a deep 

 notch before the eyes : eyes widely divided, giving 

 the appearance of four eyes, two being above and 

 two below : mouth dark tawny : antenna? short, 

 cylindrical and stout : thorax the breadth of the 

 elytra : the elytra very convex, punctured, shining 

 and covered with fine tawny pile or hair, of a 

 beautiful silky appearance. The under part of this is 

 of a dark tawny, and shining : anterior feet long, the 

 middle and posterior short, fiat, and when extended 

 scarcely reaching beyond the margin of the elytra. 



Inhabits rivers and running streams, but has not 

 been found near London. 



Length from 3 to 3| lines. 



The GyrindcB frequent lakes and still waters, run- 

 ning swiftly in circles on the surface, and when they 

 dive," carrying along with them a bubble of air, which 

 appears like quicksilver. The female deposits her 

 eggs in lows on the leaves of water grasses, which 

 are hatched in three weeks ; the larva is at first 

 transparent, afterwards dark coloured with a light 

 fascia. About August it creeps to the tops of aquatic 

 plants, and weaves about itself a web like paper, in 

 which it turns to the pupa. 



10-1 23 



