Proceedings 59 
over Imm. and at the free end between 2mm. and 3mm. The 
caterpillar never ventures outside the tube and is very timid, 
darting with wonderful rapidity down the tube when alarmed. 
Pupation takes place in the tube, a bulb 5mm. in diameter 
being formed in the middle, the tube by this operation being 
shortened to 6cm. in length. 
Amongst the Brazilian Psychids we have the genus Orketicus 
the larve of which make protective coverings of silk and bits 
of stick, etc., woven into a very strong fabric. In O. Airbii the 
case is, when the caterpillar is full-fed, 8 or g centimeters in 
length and 2 or 3 centimeters in diameter at the thickest part, 
tapering to about 1 centimeter at the lower end. 
I was fortunate enough to see the young larva just emerged 
from the egg make its first coat. I followed the whole operation 
through a lens, as described in the following note made at Sao 
Paulo in 1880. 
On January 17th I found a brood of the larve just out of 
the egg, and I determined to watch them carefully and see if 
possible the first steps in the formation of the protective cover- 
ing. After a little while I observed that one individual was 
about to begin operations, so I brought my lens to bear upon 
him. 
The first thing he did was to cut about a dozen minute 
pieces from the epidermis of a leaf of the Guava on which I 
had found the caterpillars; these were carefully collected and 
kept together by the feet. When a sufficient quantity was ready 
they were strung together with silk, the string thus formed 
being attached at each end to the leaf, but left free in the 
middle. The caterpillar then turned ‘head over heels’ through 
the loop. One end was then cut from the leaf and bound round 
the body, making a girdle between the thorax and abdomen, 
the other end of the loop still being attached to the leaf. The 
cutting of material was then resumed, and each time a piece 
was cut it was added to the thoracic side of the girdle and bound 
to it with silk. After a short time the girdle was cut loose from 
the leaf and the building up of the case went on with order 
and regularity. As the band grew in width it was pushed back 
towards the ‘tail’ and, always increasing in diameter, gradually 
