252 Annals Entomological Society of America [Vol. V, 
anterior one being very slight. This constitutes the large 
intestine. The above shape and form holds true only when the 
intestine is completely empty and relaxed. Excreta within 
will cause the large intestine and rectum, which follows, to 
assume various shapes. 
Suspensory Muscle of the Large Intestine —These two muscles 
(s. m.) extend from the ventral side of the cephalic margin of 
the caudal enlargement of the large intestine to the latero- 
ventral portion of the transverse conjuctiva, between the sixth 
and seventh abdominal segments. These two cord-like muscles 
can be best seen from the ventral aspect. 
Rectum.—The rectum (re) is the caudal termination of the 
alimentary canal and occupies the caudal portion of the seventh 
abdominal segment and the entire portion of the eighth. The 
rectum is the largest in diameter of all the portions of the 
alimentary canal. On the dorsal surface of the rectum, there 
are located two prominent, longitudinal bands of muscles that 
converge at the cephalic end of the rectum and connect at their 
caudal end to the body wall. By means of the contraction of 
the rectum, the characteristic form is given to the excreta of 
lepidopterous larva. 
Trachee of the Alimentary Canal. (Fig. 7, t)—The tracheze 
of the oesophagus and pharynx are very small and their arrange- 
ment is difficult to trace. From the adjacent first six abdominal 
spiracles there is a fan-like arrangement of tracheal branches 
which enter the lateral, folded area of the ventriculus. These 
tracheee support the ventriculus and supply it profusely with 
air. Tracheze from the seventh abdominal segment lead to the 
large and small intestine and the cephalic area of the rectum. 
However, the rectum obtains most of its oxygen by means of the 
trachez coming from the eighth abdominal segment. 
URINARY SYSTEM. 
The urinary system (Figs. 7 and 9) of Protoparce carolina is 
composed of two bladders, right and left, and their respective 
tubules. Fig. 9 shows a bladder (6) and how it enters the 
anterior part of the small intestine on the ventro-lateral portion. 
It has been pulled out of its normal position in order to show 
the place of attachment of the bladder with the small intestine. 
It turns back on itself, as in Fig. 7, and thus conceals its place 
of entrance. Leading cephalad from the small, delicate, white 
