NOTES ON BUTTERFLIES OF ADEN. 215 



and the nature of the ground made it impossible to follow it. One 

 day, however, I was on the plateau above the tanks after the sun 

 had sunk well behind the Shum-Shum Ridge, and, while hurrying 

 along to get down before dark, passed through a patch of a plant 

 (name unknown, but whose chief characteristic is the tenacious 

 manner in which the leaves cling to one's trousers), when to my 

 surprise I disturbed a specimen of T. vt, which I netted and on 

 investigation foiind that the butterfly came to roost there, the 

 underside of the insect being of the same colour as the dead leaves 

 and stalks of the plant. After some searching I got four more males 

 and two females, considerably more specimens than I had 

 taken in the six months or so previous. A big green and white spider 

 had also found out this habit and my first female was rescued 

 from its clutches. When first caught this species is of a beautiful 

 rosy salmon colour, a tint in great measure lost after death. 



28. Teracolus pleione, Klug, Symb, Phys., pi. viii, figs. 7, 8 (1 829). 

 The commonest butterfly in Aden, though, strange to say, I never 

 met with it inland. There are two forms of females, — white and 

 yellow. Colonel Swinhoe, 1. c, speaks of the former as albinos. This 

 is misleading : the white females being the normal form, and being to 

 the yellow ones probably in the proportion of three to one. I reared 

 some caterpillars feeding on Cleome, n. sp.? (This plant could not be 

 identified at the British Museum.) T. miriam, with a macular border 

 to the hindwing, appears to be nothing but a casual variety of this 

 species. At Aden these two forms fly together and interbreed freely. 



29. T, ccelestis, Swinhoe, P. Z. S., 1884, p. 435, pi. xxxix, figs. 

 1,2. 



30. T. acaste, Klug, Symb. Phys., pi. vii, figs. 16,17(1829). 

 These two forms are (almost to a certainty) varieties of one 

 species. The so-called albinos of Colonel Swinhoe, 1. c, being the 

 normal form of female, and being to the yellow ones in the propor- 

 tion of at least seven to one. 



The number of yellow females of this and the preceding species 

 appeared to me to have greatly increased between 1869 (when I 

 first collected butterflies at Aden) and 1885 (when I left on 

 completion of my second tour), and it is possible that a development 

 in this direction is steadily, though slowly, going on. 



