EXTERNAL STRUCTURE. 13 



last segments hold the genitalia in the two sexes, and also enclose 

 the sting of the females and workers in such ants as possess one. 



The genital armature of the male consists of the following parts : 

 The Annular Lamina is a ring which forms the base of the whole 

 apparatus. The External Paramera consist of the outer and inter- 

 mediate pairs of appendages ; the outer pair are the Stipites, which 

 act as claspers and are often furnished with hairs. In some genera 



Epinotum Scale 



4th 



5th 

 Gastric segments 



Pedicel 

 Fig. 24. Abdomen of Formica pratensis . 



the basal parts of the stipites consist of more or less elongate, 

 triangular, oval or semi-circular lobes, which are called the 

 Squamulae. These sometimes look as if they were separate plates 

 applied to the stipites, but this is not the case as they are actually 

 part of them. 



The median pair are known as the Volsellae, these are sometimes 

 more or less divided into two pairs, one of which is then called the 



Dorsal gastric segments 

 Epinotum Scale 1st 2nd 3rd 4th 5th 6th 



Penicilli 



Squamula 



Stipites 

 I / "" 



Pedicel $ 



r- 



Ventral gastric segments 

 Fig. 25. Abdomen of Formica pratensis $. 



Laciniae and the other the Volsellae. The volsellae and laciniae 

 also probably act as claspers. 



The Internal Paramera consist of the innermost pair of append- 

 ages, the Sagittae, which are connected together by a membrane 

 the Spatha ; and the sagittae + the spatha function as a penis. 

 The sagittae often have serrated edges which probably serve to 

 hold them in position during copulation. 



