232 Hybrids of Bidonine Moths 



Five of the hybrids, 



L. hyhr. pilzii, 

 P. hyhr. hunii, 

 L. hyhr. hurrowd, 

 P. hyhr. hulli, 

 L. hyhr. adkini, 



yield the two sexes in approximately equal numbers. 

 Three hybrids, 



P. hyhr. langei, 

 I. hyhr. harrisoni, 

 P. hyhr. merana, 



give a large excess of females. 



Lastly, the sole form reared from a hybrid J , i.e. hyhr. hrooksi, gives 

 specimens which are hopelessly gynandromorphic, wings, body, genitalia, 

 antennae being built up of parts chosen at random, as it were, from 

 both sexes of the parents and grand-parents. It is worthy of note that 

 the larger and more robust the specimen, the more the male characters 

 predominate and vice versa. 



(7) The U'udency for the hyhrids to emerge long hefore the parent 

 species. 



In most of the hybrids, it appeared that the emergence was hastened 

 by a period varying from a fortnight to three months. Most curiously, 

 this varied with the sex for, in most cases, the acceleration noted in the 

 case of the females was very great compared with the slight displace- 

 ment seen in the males, although the divergence was never so great as 

 that observed in hybrid rohsoni = Larentia (Oporahia) dilutata ^ x Lar. 

 (0.) autumnata % . In this case, the females appeared about four and a 

 half months before the males and a similar period before both sexes of 

 the reciprocal cross rungei = X. (0.) autumnata </ x Z. (0.) dilutata J. 



It is not my intention to give here my thoughts on the import of 

 this, nor what appears to me to be the significance of the sex proportions 

 detailed above. I hope to be in a position to publish my paper (already 

 planned out) before long. 



(8) The wing development oftlte hyhr id females. 



The hybrid females, when produced, vary greatly in their wing 

 development ; those between hirtaria, fully winged, of course, in both 

 sexes, and one of the so-called apterous species, possess wings varying 

 enormously even within the limits of the same brood. This is a distinct 



