450 MV. G. A. K. Marshall on 



H. The attenvpt to cotUrol flic I'hases of P. sesamus and 

 P. archesia hy the artificial ajJj^lication of Moisture 

 and Heat to the earlier stages. Suggested lines of 

 UxiJcrimenf . 



All the experiments hitherto made by Mr. Marshall were 

 directed towards the production of tlie wet natalensis and 

 ]3elasgis phases in place of the dry sesamus and archesia 

 respectively. .The whole of the specimens produced were 

 presented by Mr. Marshall to the Hope Collection, and all 

 are tabulated below, tosfether with a statement of the 

 experimental conditions Avhich were employed in each 

 case. All experiments were made at Salisbury. 



The following extracts from Mr. Marshall's letters refer 

 to some of the experiments on sesamus: — 



" Salishiiry, June 5, 1898. — I kept two larva3 in a damp 

 jar, but one did not attach itself properly when pupating, 

 and the resulting pupa fell down when soft and was 

 killed. The other larva produced a black pupa which 

 emerged as the wet form [April 13, 1898, in the Table 

 below], but this was rendered nugat(jry by the fact that 

 one of the larvse in normal conditions produced the same 

 form, though from a gilded pupa [April 20, 1898, in the 

 Table below]." 



" Salisbury, April 25, 1899. — I have fourteen bred 

 specimens of P. sesamus which I will send later [specimens 

 in year 1899 in the Table below]; I tried some experi- 

 ments with them, but the results are mostly negative. 

 There are tw^o interesting varieties, one with a red bar in 

 tlie discoidal cell and another with the red spots much 

 reduced." 



