42 Dr. Roxburgh's Account of- 
are derived from the same insect originally, and that they have* 
assumed different habits by different modes of culture or food. 
" When I return from Calcutta I shall make particular inquiries 
on the subject. 
" You will observe that the inclosed specimen is tinged of a 
deeper colour than the filament of the cocoon : this they say is 
from the alkaline ley." 
The same gentleman (Mr. Atkinson) has, since writing the fore- 
going letters, sent me large supplies of the cocoons of both the 
Bughy and Jarroo insects, and I have received parcels of them 
from other quarters. These have all produced their insects; 
and after minute investigation I am not able to observe any 
difference, except in the size, and that is even trifling, so that 
I can at most only call them varieties of the same species. But 
very different is that which lives on the leaves of the Palma 
Christi plant, a species I am now able to give an account and 
drawings of, having often reared and conducted them through 
their various stages in my own room within these three years. 
THE ARRINDY SILK-WORM. 
PHALi&NA CYNTHIA. 
Drury, 2. t. 6./. 2. 
Cramer, 4. t. 39 -Jig- A. 
Antennae pectinated ; no mouth ; wings incumbent, and ex- 
panded, with their angles rounded : superior pair falcated, with 
a black eye near the exterior angle. Prevailing colour brownish, 
with white and ferruginous curved bands ; and an obscure, semi- 
lunar, subdiaphanous mark near the centre of each. 
This 
