328 INSECTS AT H03IE. 



can be found adherino^ to twiVs, and from them the insects can 

 bo procured in considerable numbers. I find, on examining a 

 series of tliese cocoon-masses, that the number of individual 

 cocoons is somewhere about one himdred and fift3\ 



When tlie pupa changes to its perfect form, it gnaws a round 

 hole at one end of the cocoon, so as to cut out a sort of lid, by 

 raising which it can escape. Wry often, the inverted lid is 

 left in the cut end of the cocoon and closes it. The average 

 length of the cocoon-cluster is nine-tenths of an inch, its width 

 nearly a quirt er of an inch, and the depth of cell one-tenth of 

 an inch. The insects are pale and shining yellow, with the 

 upper part of the abdomen and end of the thorax black. 



We now come to the great family of the Chalcididse. 

 These insects are parasitic, are for the most part exceedingly 

 small, and many are very tiny indeed. The head is trans- 

 verse, the eyes set on the sides, and the antennae are short. 

 The upper pair of wings are almost without nervures, though 

 the course of one or two can be traced by careful examination 

 with a microscope. The lower wings have only a single nervure. 

 They are parasitic insects, many of them being actually para- 

 sitic upon other parasites, and some depositing their eggs in 

 various galls, where tliey feed upon the rightful inhabitants, 

 and in due time make their appearance, to the great perplexity 

 of practical entomologists who have kept the galls for the pur- 

 pose of rearing the particular Gall-flies which belong to them. 



One of these insects, called Cleonymus macull'pennls or 

 depressus, is shown on Woodcut XXXII. Fig. 4. 



It is a very pretty little insect, the colour being a deep 

 metallic blue, changing to green and pink according to the 

 variation of the light. The antenna3 are red, tipped with black, 

 and the abdomen is flattened, a characteristic which gained for 

 it the name of depressus. The wings are prettily mottled 

 with brown, as seen in the illustration. Mr. F. Smith says 

 that he has often seen it running quickly about posts and rails, 

 busily engaged in prying into every orifice, probably for the 

 sake of detecting some wood-boring insect, in whose body it 

 can lay its eggs. 



In this genus the thorax is rather long and egg-shaped, the 



