190 Dr. F. A. Dixey on 



that C. crocale and C. pomona (including C. catilla) will 

 prove to be seasonal forms of one species." * Direct 

 evidence on the point was, however, lacking; and I 

 therefore welcomed a statement made later by Batchelor 

 in a letter from Brisbane, and kindly communicated to 

 me by Professor Poulton, that G. crocalc and C. 2')omona 

 were one species, " crocalc being the summer brood and 

 pomona the autumn one." It does not appear that any 

 observer has as yet actually bred one form from the other, 

 so that it cannot even now be said that their specific 

 identity is proved with absolute certainty. Nevertheless, 

 the opinion of a collector who has taken large numbers of 

 both forms is of weight, and may safely be held to indicate 

 a strong probability that, at all events in part of their 

 range, C. 'pomona, Fabr. and C. crocalc, Cram, are seasonal 

 phases of the same species. 



It is, however, evident that the case v^ith regard to 

 C. pomona is not quite a simple one. In the autumn of 

 1900, a series of eighteen specimens of Catopsilia was 

 received by the Hope Professor at Oxford from the late 

 Mr. L. de Niceville, who stated that they were all caught 

 nearly at the same time in the Kangra Valley, Western 

 Himalayas, by Mr. G. C. Dudgeon. Of these eighteen, 

 sixteen were taken on August 11, and the remain- 

 ing two on August 13, 1900. Two of the captures on 

 August 11 were Catop)silia pyranthe, Linn. ; and of the 

 remainder, eight were C. crocalc, Cram., and six were 

 G. pomona, Fabr. Those caught on August 13 were 

 G. crocalc ^ and C. p)omona $ taken in copula. In two 

 private letters to the Hope Professor, Mr. de Niceville 

 appeals to this series of specimens in support of the 

 view that C. pomona f and G. crocalc constitute one 



* Proc. Ent. Soc. Lond., 1898, p. Ixxvi. It is hardly necessary 

 to recall the fact that this address of Mr. Trimen's contains an 

 excellent account of nearly all the experiments and observations 

 that had been made on the subject of seasonal dimorphism in 

 butterflies up to the time of its delivery. 



t De Niceville calls it G. catilla, Cram.; but the latter name, 

 under which Cramer figures the form with brownish-crimson patches 

 on the under-surface (see Cramer, Pap. Exot., III. t. 229, D, E), is 

 later than that of Fabricius. Fabricius's type still exists in the 

 Banksian cabinet, where I have examined it in concert with Dr. A. 

 G. Butler. The six sj)ecimens of G. pomona caught on August 11 

 include two G. catilla, Cram. The British Museum contains six 

 specimens of G. crocale and seven of G. pomona caught by Mr. 



