136 NATURAL HISTORY OF 



hairs, and no doubt assist materially in swimming. 

 The food of the larvae is similar to that of the per- 

 fect insect, and they are perhaps even more vora- 

 cious in their early condition than after they have 

 undergone their final change. The following cut 

 represents the larva of Dytiscus marginalis, the 

 most common species throughout the southern parts 

 of Britain. 



The largest species of Dytiscus with which we 

 are acquainted is D. latissimus, which is found in 

 Germany and the north of Europe. About eight 

 or nine different kinds inhabit Britain, some of 

 which are common in England ; but they become 

 scarcer in the more northern parts of the island. 

 The species represented, for which we are indebted 

 to Mr Curtis' beautiful figure, is 



