1302 Rocer C. SMITH 
line at the posterior part of the prothorax. This occurred six minutes 
after the abdomen was cemented to the slide. The split lengthened 
‘rapidly, both anteriorly and posteriorly. At the same time the thorax 
began to arch, the head was bent ventrad, and the abdomen was pulled 
forward. In two minutes more the mouth parts were very carefully and 
slowly withdrawn. The head was lifted slowly with the arching of the 
thorax, and during this process the legs were being withdrawn also. 
The tracheal chitinous intima was drawn out through the spiracles as 
hollow threads. The jaws and the antennae freed, the legs were pulled 
entirely out, the metathoracic legs being the last to appear. By this 
time the abdomen was practically out of the skin. The whole process to 
this stage required eight and a half minutes. As the old skin moved 
backward, the setae, folded across or around the body, thus freed, sprang 
into their normal positions. 
The newly molted larva is very helpless, similar to its condition at 
hatching. The legs cannot be used. The head is bent ventrad and 
eaudad. The larva holds fast to the molted skin by means of the anal 
proleg, which constitutes its only support while the new chitin is hard- 
ening. The legs are pulled up and then extended occasionally, and the 
head is slowly lifted to a horizontal position. The larva under observa- 
tion rested on its legs and the head was in the normal position in twelve 
minutes from the beginning of the molt. 
The old larval skin remained attached to the slide, the end of the tail 
being flattened and glued fast. There was a rent in the east skin from 
the mesothorax to the head; in fact, only the venter of the thorax 
remained intact. The legs were pulled up and were wholly under the 
venter, except the last pair, which protruded slightly. The black patch 
on the head was retained. It is generally possible to name the species 
of the larva and the instar from the old larval skin. However, the 
color pattern is not well retained. In rearings, the molted skins were 
usually found in the vials adhering to the glass or to the cotton plugs. 
The coloration of the body is that which is characteristic of the instar. 
The color pattern is distinct, of the greatest intensity during the instar. 
The grays at this time appear white to semi-translucent and often 
yellowish. The color pattern on the head is represented at molting, as 
at hatching, by an indistinct brownish patch. After an hour the out- 
line of the black patch is distinet, but from two to four hours must pass 
before the normal head and body coloration is complete. The mouth 
parts, palpi, antennae, and legs are from wholly hyaline to translucent. 
The tips of the jaws become yellowish brown in an hour. The darkening 
of the leg segments appears slowly also. 
