1912] Anatomy of Tomato-worm Larva 247 
parts. Staining the tissues with a weak solution of Delafield’s 
hematoxylin was found very useful in differentiating the finer 
structures. This was especially true in working with the 
nervous and circulatory systems. The resulting light-bluish 
coat given to the tissues, when not stained too deeply, proved 
to give the best results. Stained material will retain the stain 
for three or four days without becoming muddy and indistinct. 
To stain a certain area, the obstructing material was cleaned 
away and rinsed clean with running water. Pouring off all the 
water, two or three drops of the stain were dropped on the 
moist parts. The stain in no case was allowed to remain on 
the tissues over thirty seconds. As a general rule, the surplus 
stain was immediately washed off with running water. 
The various parts of the larva will be discussed in the 
following order :— . 
A. External Anatomy :—Head, Thorax, and Abdomen. 
B. Internal Anatomy :—Adipose Tissue, Digestive System, 
Silk Glands, Salivary Glands, Respiratory System, Muscular 
System, Circulatory System, Reproductive Organs, Wing Buds, 
and Nervous System. 
A. External Anatomy. 
The larva of Protoparce carolina when mature is approxi- 
mately 9-enr. in’ length and 12-15 mm. in diameter: » It hasia 
distinct greenish cast with diagonal lines of dark brown, pig- 
mental blotches, which extend from the dorso-caudal part of 
each abdominal segment ventro-cephalad. The body is divided 
into three regions, head, thorax, and abdomen. 
Heap (Figs. 1, 2 and 3).—The head is the smallest division 
of the body. It is a non-wrinkled, yellowish-white region, 
which from a lateral or ventral aspect is oval in outline, while 
from a cephalic view, it is spherical. On the median portion 
of the cephalic aspect, there exists a distinct inverted Y-shaped 
suture (e), the epicranial suture, which divides the fixed parts 
of the head into three regions. Connected with the ventral 
part of the region included within the arms of the Y, are the 
mouth parts. The large areas laterad of the epicranial suture 
have on their ventral aspects the antennz and simple-eyes. 
Eyes—The simple eyes (0) consist of two groups of six 
ocelli, five of which are arranged in a semicircle with the sixth 
on the median part of the diameter of the circle. These groups 
