ThE STREPSIPTERA. 



387 



of these minute parasites had already been discovered. One of 

 the largest species {Stylops Spencii) is scarcely more than two 

 lines in length, while the smallest species yet known is not more 

 than two-thirds of a line, or scarcely a line in breadth with its 

 wings expanded. They undergo metamorphosis, and the males, 

 when they have become perfect insects, fly and roam about, but 

 the females are condemned to a perfectly quiet life. The head 

 and the thoracic segments of the bodies of these last are united 

 completely, but the abdomen, which is very large, always remains 

 very soft, so that the whole of the body only appears to be formed 





Stylops aterrimics. the male. (Natural size and magnified.) 



of two portions. They are ovo-viviparous insects, and the young 

 larvae escape as such from the body of the mother. They are active 

 creatures, and, being furnished with long legs, crawl over the hairs 

 and skin of the hymenopterous insect they are parasitic upon. 

 They behave like the larvae of Mdo'e and Sitaris, whose peculiar 

 methods of life have been noticed in our description of the Coleop- 

 tera. Clinging on to a wasp or a bee they are carried off and 

 finally arrive in the nest or hive, as the case may be, and there 

 they attack the larvae. When once fixed upon the hymenopterous 

 larvae they undergo a change of skin, and their shape then becomes 

 totally different, and their legs are atrophied. But these parasites, 

 being exceedingly small, do not kill the larvs ; they suck their 

 juices after the manner of the Ichneumons, and do not interfere with 

 the metamorphoses of the insects upon which they are parasitic. 



z 2 



