138 



FOREST ENTOMOLOGY. 



of the Cynipidae are complete. They pass through four stages viz., 

 egg, larva, pupa, and imago (fig. 129). 



The egg (fig. 129, a) is pyriform, with one end elongated, terminat- 

 ing as a prolonged penduncle. Adler supposed the function of this 

 organism to be respiratory, it having long peduncles when deeply 

 embedded and difficult of access to oxygen, and shorter when access 

 is easy. 



The eggs of the Cynipidae are often laid in winter, thus contrasting 



Fig. 129. 



Egg of Cynips. (Copied from Adler and 



Stratton.) 

 6 Larva of Cynips. 

 c Pupa of Cynips. 

 d Gall-fly, Teras tcrmimdis (oak-apple). 



Male. (From photograph.) 



e Ovipositor of Neuroterus lenticularis. 



(From camera-lucida sketch.) 

 / Wing of Spathegaster baccarum. (From 



photograph.) 

 g Antenna of Spathegaster baccarum. (From 



camera-lucida sketch.) 



with the eggs of many species of saw-flies, which are deposited when 

 nature is active. There are other interesting points about the eggs 

 which will be considered later on. 



The larvae are white, footless, and fleshy grubs, with thirteen 

 segments (fig. 129, b). There is considerable diversity of time regard- 

 ing the larval stage. 



In appearance the pupge are similar to the larvae, and some organs 

 of the perfect insect are discernible. Fig. 129, c. 



