140 JOURNAL OF ENTOMOLOGY AND ZOOLOGY 
radula, as the cavity narrows. About half way between the 
two ends of the buceal mass the cesophagus branches off on the 
upper side, but the buccal food cavity does not end when this 
takes place, but extends as a blind pocket nearly to the end of 
the buccal mass. 
Close to the point where the cesophagus branches off, minute 
ducts from the salivary glands enter the buccal food cavity, one 
on each side. These glands are long, unbranched tubes, lined 
with cubical epithelial cells. They lie loosely in the body cavity 
back of the buccal mass, and in two specimens examined the 
ends were fused. 
After leaving the buccal mass the esophagus goes back be- 
tween the ganglia of the central nervous system, gradually be- 
coming larger, passes below the liver, and enters the stomach on 
the under side. The stomach itself is rather small but communi- 
cates with the liver by numerous large openings, so as to make 
its actual capacity considerably larger. The stomach is lined, 
as are the cesophagus and intestine, with ciliated epithelium. 
The liver consists of branching tubes lined with tall columnar 
cells with a fine granular protoplasm. On the upper side of 
the stomach is a cecum, about twice as large as the intestine, 
in diameter, which is lined with glandular cells of a different 
character than those of the liver. Directly in back of this 
cecum the intestine leaves the stomach. It runs forward over 
the surface of the liver to the extreme anterior end, then curves 
to the right and runs back to a point just beneath the branchie, 
where it becomes slightly enlarged and laminated and curves 
upward to open within the circle of the branchial plumes. 
Tue Nepuripium. The kidney is a thin-walled sac with many 
ramifications that cover the whole surface of the liver mass and 
extend for a short distance down the sides. The walls are 
formed by a single layer of large, cubical granular cells on a 
very thin basement membrane. These contain round, dark- 
staining nuclei and a small amount of protoplasm near the base, 
the rest of the cell usually being clear. The kidney communi- 
cates with the pericardium near the point where the right 
lateral sinus enters the right auricle, by means of a tubular 
