320 INSECTS AT HOME. 



CHAPTER II. 

 THE ICHNEUMON FLIES. 



We now come to the Ichneumonidup, one of the largcr^t, most 

 important, and most perplexing groups in the insect world. 

 They are termed Ichneumonidte, or Ichneumon-flies — because 

 they enact the same part towards various insects tliat the iclmeu- 

 mon was said to act towards the crocodile. They are parasites 

 upon other insects, and for tlie most part they spend their 

 larval existence within the l)odies of tlieir victims, where they 

 lurk unseen and imsuspected until the time comes when they 

 have to change their forms. In this family the abdomen is 

 attached to the end of the thorax, and not to its upper part, 

 as in the Evaniidoe, and the first pair of wings have always 

 'perfect' cells, i.e. cells closed on all sides within their disc. 

 The ovipositor of the females is straight, and the antennae are 

 not elbowed. There are many other cliaracters of this family, 

 but these are sufficient for identification. 



The first and typical genus of this family is Ichneumon, in 

 which the abdomen is rather egg-shaped but oblong, and the 

 ovipositor is not external. The antennre are linear, and the 

 wings have the areolet five-sided and boldly marked. The 

 outer cell is complete. 



Our first example of this genus is given on Woodcut XXXI. 

 Fig. 1, and is called Ichneumon proteus. Why it should have 

 obtained the name of Proteus is more than I can understand. 

 ■ The name decidedly implies that it is exceedingly variable in 

 -some way, but in a long series that I have examined I could 

 not find any variation worth noticing. The colour of this 

 insect is black, with a yellow scutellum, and a yellowish patch 

 in the middle of the antenna?. The wings are translucent, but 

 •jfiha'ded toward the tips. 



.'At-Ficf. 2 of the same Woodcut is shown the male of another 



