THE IIYMENOPTERA 



351 



body, in these punctures, and the larvae which hatch from the eggs feed 

 upon the chrysalis, finally killing it about the time they become full- 

 grown. They then leave the chrysalis and spin small, white cocoons, 

 usually in a rather compact mass somewhere near what remains of their 

 deserted host, emerging from these cocoons after a time, as adults which 



Fig. 366. — Pteromalus puparum L., a Chalcid parasite of the Cabbage Worm and 

 other insects: male (left), and female (right). Hair lines show the natural size. {After 

 Ckitlcndcn, U. S. D. A.) 



start another generation. It has been discovered that egg-laying in this 

 species (and in many other parasites also) may continue during quite a 

 long period provided the adult can obtain food, and this in many cases at 

 least is accomplished by puncturing the body of the insect in which eggs 

 are to be, or have just been laid, and feeding on its juices. 



Swperjamily Serphoidea. — This superfamily, long known as the 

 Proetotrypoidea, contains a large number of insects, nearly all very 



Via. 367. — Pelecinus polylurator Dni.: a, female; h, male. Natural size. (Uriginal.) 



small, and most of them parasitic on other insects or on spiders. Para- 

 sitism of insect eggs seems to be very frequently the habit in the 

 group. Some of the forms attacked by this group are Hemiptera, 

 Diptera, Orthoptera, Lepidoptera, Neuroptera (Aphis lions) and Cole- 

 optera, and some are found in ants' nests, parasitic on these insects. 

 None of the members of the Superfamily is liable to attract the attention 

 of those not entomologists, with one exception, an insect known as the 

 Long-tailed Pelecinus {Pelecinus polyturator Drury), the female (Fig. 367a) 

 of which has a long, slender body often between two and three inches long, 



