INTERNAL STRUCTURE. 



23 



and in these the eggs are formed. The ovarioles are attached at 

 their narrow ends to the pericardium, which lies immediately under 

 the basal tergite of the gaster. 



The number of ovarioles in each ovary varies considerably in 

 different species in the female of Aner gates atratulus they consist 



Receptaculum 

 glands 



Accessory 

 gland 



Sting 



Vagina 

 Bursa copulatrix 

 Fig. 39. Reproductive organs of Myrmica rubra $. (Janet.) 



of 12, Myrmica laevinodis 12, M. ruginodis 8, M . scdbrinodis 8-9, 

 M. sulcinodis 9-11, Donisthorpea nigra 30-40, D. flava 24, Formica 

 rufa 45, and F. rufibarbis 18-20, etc. 



The ovaries are present in the worker also, the number of ovarioles 

 however being considerably reduced. It has been estimated for 



Fig. 40. Ovaries of pseudogyne of Formica rufa. 



each ovary in Myrmica laevinodis^ ruginodis and scabrinodis as 1, 

 Tapinoma erraticum 1, Donisthorpea fuliginosa 1-2, D. flava 1, 

 Formica rufa 4-10, F. pratensis 2-6, F. sanguinea 3-6, etc. 



The receptaculum seminis is usually wanting in the worker, though 



