254 N - J- KfSXEZOV. 



bears a process having three teeth quite similar to those on the 

 tips of the normal valva (Fig. 10, pr. v.}. Under this valvoid 

 there are some minute sclerites disseminated over the inter- 

 segmental membrane of the tube of the ductus bursae. From 

 their consistence and structure they also may be considered as 

 crushed rudiments of the male valva. 



Thus, in this case we observe a predominance of female charac- 

 ters in the form of both fore tarsi and almost all parts of the 

 copulatory apparatus which are but slightly deformed. Male 

 features, represented only by rudiments of valvae, are nevertheless 

 situated on the same side of the plane of bilateral symmetry as the 

 male wings. 



In all described gynandrous individuals, however similar in their 

 external appearance which is that of common halved gynandro- 

 morphs, quite different interrelations in the degree of development 

 and disposition between the secondary and tertiary * sexual 

 structures are observed. My present observations, as well as 

 previous (1916), mentioned above, permit me, I think, to draw 

 the following conclusions. 



The division of the tertiary sexual structures into two halves by 

 the plane of bilateral symmetry may be associated : 



(1) With a division of the paired copulatory structures by this 



plane into two pretty normal halves, the unpaired organs, 

 like penis, bursa and their ostia being developed nearly 

 normally; the case of Pieris rapx L.; 



(2) With a more or less complete unisexual! ty of the genital 



structures: male, as in my cases of Malacosoma neustria L. 

 (complete unisexuality) and Dendrolimus pini L., or 

 female, as in Lycxna argus L. ; 



(3) With an intermediate position, where the structures of one 



sex are intermingled with those of the opposite sex on both 

 sides of the body; these are the cases of Pygxra timon 

 Hbn., Bupalus piniarius L., Gonopteryx rliamni L., one sex 

 being rather more strongly developed than the other; 



(4) With a division of the paired copulatory organs in respect to a 



frontal plane of the body, with the presence of the unpaired 



1 Under the term of secondary sexual structures is meant the copulatory organs or 

 genital ia, under that of tertiary the locomotor apparatus, pigments, sense organs and 

 their accessories. 



