E. A. Cockayne 



107 



luaturity laid a variable iiuinbcr of ova, if they possessed one or two 

 ovaries. 



The authors regard tliis as an attempt to produce a bisexual genera- 

 tion, and this seems to be the most likely explanation. In these 

 parthcndgenetic insects the ova undergo no reduction divisions until 

 a bisexual generation is formed. 



An eiior of lueiosis might give rise to a halved gynandiomorph. 



Diagram /■. Diagram j. 



Diagram j'. Agruules coridon. Caput bursae, ductus seminis absent. One cement gland 



atrophic. 

 Diagram A-. Agriades coridon. Three ovarian follicles instead of four on each side. 

 1, Ovary; 2, oviduct; 3, receptaeulura seminis ; 4, ductus seminis; 5, bursa copulatrix; 



6, caput bursae; 7, cemeut gland. 



Hereditary G y nandroiunrpJm m, probably of Direct Descent. 



Even more remarkable is the race of Agriades coridon, which 

 inhabits a small isolated range of chalk downs in North Hertfordshire. 



There are other isolated chalk hills to the north-east and to the 

 west, also inhabited by coridon. In the Hertfordshire locality females 

 always greatly exceed males in number, .sometimes as many as ten or 



