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XXVI. Some breeding experiments on Catopsilia pyranthe 

 and notes on the migration of Butterjiics in 

 Ceylon, by Major Neville Manders, R.A.M.C, 

 F.Z.S , F.E.S. 



[Read May 4th, 1904.] 



Plates XXXIV and XXXV. 



The following experiments were preliminary to a more 

 thorough investigation. 



I had hoped to have ascertained with exactitude the 

 amount of heat, cold and moisture necessary to produce 

 the various forms in which this insect occurs. The ex- 

 periments were merely preliminary in order to ascertain 

 the difficulties and the apparatus required to carry out a 

 thorough investigation. They may be of interest because, 

 as far as I know, they are the first experiments made with 

 icing the pupse of a tropical butterfly. Even these pre- 

 liminary experiments are far from being complete, as I 

 was ordered home when in the middle of them and had 

 to hand over my notes and material to another ento- 

 mologist, Mr. Oswin Wickwar, who did what he could in 

 the intervals of a busy official life. 



Catopsilia pyrantlie occurs in Ceylon under many 

 different forms, three of which besides Pyranthe have 

 received names, namely, Ilea, Choyseis and Glioma. 

 Gnoma is usually called the dry-season form and Chryseis 

 the wet, and though Gnoma is certainly more common 

 in the dry, it is by no means confined to the dry months, 

 neither is Chryseis confined to the wet. It may be said that 

 all the forms occur indiscriminately all the year round, 

 and my first object was to ascertain which was the dry 

 form and which the wet, and what would be the several 

 effects of heat, moisture, etc. on the larvas and pupse. The 

 first thing was to ascertain the proportion of each variety, 

 and this I left in Mr. Wickwar's hands, and in the month 

 of February 1903, during a migratory flight, he captured 

 sixty specimens, the weather at the time being very dry 

 and hot. 



He mentions (and I will allude to this later) that 75 

 per cent, were males, and (j4 per cent, of the total were 



TRANS. ENT. SOC. LOND. 1904. — PART IV. (DEC.) 



