124 
Psyche 
[June 
on Plate III fig. 1 and is the largest and most conspicuous form 
known so far. 
Since 1922 I had a large number of the larvae under close 
observation and have made every effort to rear them. The first 
species that came in my way was the large attractive larva just 
referred to above. It was found quite commonly on the higher 
slopes of the unknown Mt. Murad, a high mountain situated in 
the North of Sarawak not very far from the Dutch boundary. 
Over 200 specimens in different stages were secured and kept 
alive in suitable cages, but none of them underwent any meta- 
morphoses. Most of them were brought along six weeks later on 
when I returned from Mt. Murad on my way back totheBaram 
Station on the lower Baram River. Owing to the awkward 
conditions of transportation where everything had to be carried 
on the natives’ backs, many of the larvae died. 
The sudden change in temperature from the cold mountain 
regions down to the steaming hot lowland naturally aided in 
reducing the number. 
In January 1923 I undertook an expedition to Mt. Dulit 
(4000-5000 ft.). The number of surviving larvae, about 30, 
were taken along, but soon died. Out of more than 200 larvae 
only a single one developed into an adult female, distinguished 
from the full-grown larva only by possessing a sexual opening in 
front of the anal disc, surrounded by two simple genital valves. 
It lived for some days but owing to some difficulties in casting 
the skin on the apical segments it soon shriveled, became dis- 
colored from a black secretion and died. 
A dissection showed the ovaries full of small whitish eggs, 
convincing me that I had to do with a sexually mature, fully 
developed female for the first time. 
When arriving at Mt. Dulit on the Tinjar River, a large 
tributary to the Baram River, I found to my great surprise that 
another “trilobite-larva” of large size and of apparently unknown 
type was fairly common on the higher slopes from 3500-4500 feet. 
It is the big black larva of the type shown in Plate III fig. 2. 
On returning to my headquarters in Kuching in March I 
brought more than a dozen very large larvae with me. These 
were fed on decaying jungle wood, which was changed daily. 
