lvii, lviii] CoSatiny?) 
hail, and all species of butterflies were going to rest unusually 
early. It is very unfortunate I have not been successful in 
getting any ova from the 9s kept for this purpose, but even 
had I done so, I am not at all sure that I know the food 
plant. Roland Trimen, F.R.S., in his work suggests a tree, 
but [think that the Buck Weed is far more probable, as nearly 
all the recorded specimens were settling on or flying over this 
plant. I several times searched unsuccessfully for the pupa- 
cases, although a great many of the wah/bergi had scarcely 
dried their wings when captured, and in several cases I 
observed on the leaves beneath the spot where a butterfly had 
been resting the excretory fluid which is ejected shortly after 
emergence, 
Professor Poutton also exhibited Mr, Guy A. K. Marshall’s 
latest demonstration of seasonal phases in South African 
species of the genus Precis—the proof, by actual breeding, 
that P. tuwkuoa, Wallgr., is the dry season phase of P. ceryne, 
Boisd. 
The female parent of the wet phase was captured April 2, 
1905, at Salisbury, Mashonaland (5000 ft.). The eggs were 
laid on the following day, and all hatched April 13. The 
eight offspring were treated, and went through their trans- 
formations as follows :— 
1905. 1905. 
1. Pupated May 9. Emerged May 27, asa dry phase ? 
2. ” ” 12. ” ” 31, ” ” 3 
3. >D ” 12. ” ” 31, oP) ” g 
4 s gfe Aba P Junet,. 5; hoes 
5 2) ” 13. ” ”? 1, ” ” 3 
15. ” 2 ” 3 
SU Gos 
” ” ” —S] ” 
. Pupated and subjected to damp heat, May 15, 1905. 
Emerged May 23, 1905, as a dry phase ¢ 
8. Pupated and subjected to damp heat, May 15, 1905. 
Emerged May 23, 1905, as a dry phase ¢ 
The whole of the offspring are marked examples of the 
tukuoa or dry phase. The damp heat to which Nos. 7 and 8 
were subjected hurried the transformation in a remarkable 
manner, the pupal period only enduring for eight days, instead 
of from eighteen to twenty days, as in Nos. 1-6. But with 
