XXVlt. 



with the costse, there may arise two long arms, each bear- 

 ing a soft hairy pad, and united together by a thin mem- 

 brane. These arms I term The Labides (Eupithecia, pi. 

 xxvii.). 



THE DUCTUS EJACULATORIUS. 



This with the vesica forms the seminal duct. Passing 

 from the vasa differentia it enters the aedceagus just above 

 its blind end. Thence it runs throughout the length of the 

 acdoeagus until it unites with the vesica (Carsia paludata, 

 pi. xlviii.). 



THE VESICA. Pierce, " Noctuida." 



This is the extrudible part of the seminal duct which, 

 (Juring copulation, penetrates into the bursa of the female. 

 It is generally scobinate and is often armed with remark- 

 able spines called The Cornuti (Deuteronomos fuscantaria, 

 pi. vi.). 



THE CORNUTI. Pierce, " Noctuida." 



These are very variable in character. Usually they 

 are strong spines grouped in clusters, but occasionally there 

 is only a single spine. Very rarely there are found articu- 

 lated spatulate spines of markedly different formation. 

 During copulation these are transferred to the bursa, but 

 I am quite unable to say what function they perform. In 

 the Geometridce we have found this form only in Gnophos 

 obscuraria, but in many groups of the Tortricida it is 

 general. Dr. Chapman has recorded a similar occurrence 

 in Pyraustra in the form of a single specialised spine 

 (" Ento. Eecord," Vol. xxv., p. 106, 1913). 



When stating the number of the cornuti in any species 

 it must be understood that only the approximate number 

 can be given. 



THE FEMALE. 



The genitalia of the female consist of : (i) The 

 Ovipositor, (ii) The Ostium, attached to which there may 

 be an Operculum. (iii) The Ductus Burses with its arma- 

 ture, (iv) The Bursa, on the armature of which the most 

 important feature is The Signum. 



