of a Species of Ornithoptera, 273 



The larva feeds on a climbing plant, not observed in flower, 

 but which has the habit and foliage of an Aristolochia* It is 

 sluggish in its movements, and feeds at intervals day and night. 

 When about to change its form it seeks some neighbouring tree 

 or shrub with a stronger and more rigid leaf, from the under 

 surface of which it suspends itself in an inclined position ap- 

 proaching to horizontal. The two ends of the suspending thread 

 are fastened at the same point on the midrib of the leaf, and the 

 loop passes completely round the insect, as in all other Papilionidce, 

 and is not fastened to a tubercle on each side of the pupa, as 

 stated by Boisduval, on the authority, I presume, of Dr. Horsfield. 

 As the larva makes the thread and attaches it before escaping 

 from its skin, any other mode than the usual one would seem to 

 be impossible. The mistake has probably arisen from the weight 

 of the pupa causing the fine sharp thread to be almost buried and 

 hidden in its newly-formed soft skin. In the pupa case, which I 

 have preserved, it may be distinctly traced round the back, 

 forming a perfect loop. 



The pupa is of a rich brown colour, on the back ochre-yellow, 

 with the points and tubercles nearly black. It is very bulky, and 

 nearly 3 inches long. Two specimens which I bred both pro- 

 duced females, and a third, also a female, was unable to free itself 

 from the pupa case. Its duration in the pupa state is exactly a 

 month (twenty-nine or thirty days), a very long period for a 

 diurnal Lepidoptera in the tropics. 



It would thus appear that there are no characters in the larva 

 or pupa to separate Omithoptera from Papilio ; but the large size 

 of the perfect insects, their long and powerful legs, the large anal 

 valve of the males, their uniform and characteristic form, their 

 striking colours and their limited geographical range, are, I 

 think, sufficient reasons why the genus should be kept distinct. 



* I have, since seen the flower. It is an Aristolochia. 



VOL. IV. N. S, PT. Vir. APR. 1858. 



