The Morphology of a Solenogastre. 709 
In this species the stomach is sharply differentiated from the 
remainder of the digestive tract and occupies the major portion of 
the visceral cavity between the hinder border of the radula and its 
supports and the anterior end of the gonad and liver. Its epithelial 
lining is fashioned into a number of heavy folds (12—15 transverse 
ridges in one specimen) that gradually blend into those of the 
oesophagus. The constituent cells throughout are essentially alike 
differing merely in height. In a typical condition each is columnar 
with basal spherical nucleus and cytoplasm packed with innumerable 
greenish-yellow granules which become intensely black after treatment 
with osmic acid. Surrounding the stomach are a very few muscle and 
connective tissue fibres some of which penetrate the epithelial folds. 
In every case the contents of this organ consisted of a finely granular 
coagulum with an occasional diatom and numbers of the large 
secretory granules that have been passed in from the liver. 
In most cases the intestine leaves the posterior end of the 
stomach close to the dorsal side in the mid line (Fig. 3) and 
immediately ventral to this union the liver opens by a separate 
single pore. This latter organ is relatively voluminous, filling much 
of the space beneath the gonad between the stomach and cloacal 
chamber where it ends blindly (Fig. 8). Its walls are provided with 
numerous irregular folds extending far into the lumen of the gland 
and are heavily laden with dark brown glandular products which 
give the animal a slaty-gray color in life. Sections show that these 
secretory products occur in practically every hepatic cell and that 
they belong to two distinct classes. All the cells in the region of 
the gonad are comparatively dense and compact, with basal nuclei 
(Fig. 10), and are almost completely filled with small glandular 
masses that become black after treatment with osmic acid but are 
little affected by carmine and logwood stains. Distal portions of 
the cells become constricted off and soon dissolve in the liver cavity. 
The glandular products of the remaining liver cells are of 
somewhat larger size and sooner or later unite to form a central 
mass that in advanced stages almost fills the cell. In these compound 
bodies the central portions ultimately become liquified and stain a 
bright crimson, while the outer portions as well as the smaller 
granules elsewhere in the cell assume a yellowish-green tint after 
treatment with boraxcarmine. With the rupture of the cell wall 
these bodies make their escape and accumulate in large numbers in 
the stomach and to a much less extent in the neighboring portions 
