The Shell-Collector’s Handbook. ll 
kidney in the Pulmonata is situated between the 
pulmonary vein and the heart, and communicates 
with the pericardial cavity by the reno-pericardial 
canal. It consists of two parts, one thin-walled and 
saccular, the other yellowish and of a lamellated 
structure. It corresponds with the Organ of Bojanus 
of the Bivalves. 
The duct of the kidney or wreter commences in its 
posterior portion, runs alongside of, but dorsad, to the 
rectum, and opens into the mantle-cavity near to the 
anus. 
The foot-gland or pedal gland is a tubular sac, lined 
with ciliated epithelium, which runs the length of the 
foot, and opens to the exterior just below the mouth. 
A similar tail-gland obtains in the genera Geomalcus 
and Arion. 
Tue Nervous System.—Lying over the cesophagus 
are a pair of pear-shaped masses of nervous tissue— 
the supracsophageal or cerebral ganglia—from which 
arise nerves which pass to the tentacles and lips, and 
a large pair of nerves—the buccal nerves—which 
course by the side of the esophagus, to end in two 
buccal ganglia placed externally to the ducts of the 
salivary glands. These buccal ganglia are united by 
a commissure from which arise nerves to supply the 
buccal mass. 
Below the cesophagus are two closely approximated 
ganglia—the subesophageal ganglia—formed of an 
anterior portion (pedal ganglia) which is divided from 
the posterior portion (viscero-pleural ganglia) by the 
passage of the aorta through the centre of the mass. 
The pedal ganglia innervate the foot, while from the 
