DYTISCUS. Q3 



space of about a minute; and even the Banstickle 

 itself, which is so great a destroyer of the small 

 fry of fishes, and so well armed for defence, is not- 

 withstanding a prey to this devouring insect, which 

 seizes it with violence, and very quickly destroys 

 it. When arrived at its full growth, the larva 

 betakes itself to the banks of the water it inhabits, 

 and forming itself an oval hollow in the soft earth 

 or clay, in a few days changes into a chrysalis 

 much resembling that of the genus Scarabseus, 

 and of a whitish colour. From this, in the space 

 of about three weeks, proceeds the complete in- 

 sect. The male, which has been described above, 

 is distinguishable not only by the smoothness of 

 the wing-sheaths, but by the far superior breadth of 

 the fore-feet, which are expanded near the tips into 

 a broad oval dilatation, concave on the lower sur- 

 face: the female, instead of being smooth, has the 

 wing-shells marked from about the middle to the 

 tips with numerous deeply-impressed longitudinal 

 furrows. 



Di/tiscus cinereus is a much smaller species, 

 and of a broader shape in proportion : the male is 

 of a blackish olive-colour, with an ochre-coloured 

 band across the thorax, which, as well as the 

 smooth wing-shells, is edged with ochre-colour, 

 while the female has those parts of a dull ash- 

 colour, strongly marked by several longitudinal 

 furrows. The larva of this species is of the same 

 general form with that of the preceding, but pro- 

 portionally smaller, and with a longer neck. It 

 is not uncommon in stagnant waters. 



