60 Proceedings 
formed a conical case, the foundation of the house in which 
the insect passes its larval and pupal stages; indeed in the case 
of the female, the imago state also, for it is only the males that 
emerge, the females remaining in the case and dying there. 
It took two or three hours to complete the cone. 
Later on in life the case is strengthened with bits of stick 
woven between the outer layer of silk and the inner lining, and 
I have often watched the operation of adding the sticks. First 
the case is attached at the mouth of the baggy upper end to the 
stalk of the food-plant, so as to leave the legs of the caterpillar 
free for building purposes; a bit of the stem of the plant of the 
required size, say 15 or 20 millimeters long is now cut off, and 
being seized by the feet is brought to the place where it is to 
be added to the case; here it is lightly secured with silk and the 
caterpillar withdraws into the case. Soon its head appears cutting 
with its powerful jaws through the side of the case where the 
bit of stick is; the stick is seized and drawn forcibly to the hole 
and bound tightly from the inside, afterwards being covered on 
the outside also with a tough cloth of silk. The stick is thus in- 
corporated in the case, between the inner and outer layers of 
silk. The intelligence shown by this caterpillar in its work is 
quite uncanny. 
In another species (O. jones?) the case is formed entirely of 
silk and mucilage, making a very strong, tough, tapering tube 
from 8 to 12 centimeters in length and about 12 millimeters in 
diameter at the upper end and 6 at the lower end. 
To illustrate the Drepanulid group I shall take only one 
species, Perophora sanguinolenta, Felder. 
This caterpillar feeds on a species of myrtle that is very plenti- 
ful in open spaces round Sao Paulo. It constructs a gondola- 
shaped case that is slung from the twigs of the food-plant by 
silk threads; when all the leaves within reach are eaten the case 
is moved by the suspending cords being cut at one end and 
fastened to a new support; the other end is then cut free in the 
same way and thus the caterpillar can reach any part of the 
shrub. 
I was not fortunate enough to observe the first stage in the 
construction of the case, as in Ovketicus, but I often saw the 
