980 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Cephalic glands enormously developed, occupying the whole thickness of the outer longitudinal 
muscular layer in the mouth and anterior esophageal regions, and making up fully three-fourths the 
substance of this layer. A short distance back of the mouth these glands begin to decrease in abund- 
ance in the dorsal half of the body, and gradually disappear, except for scattered clusters in the midst 
of the outer longitudinal muscular layer in the ventral half of the body (fig. 1, eg'). They disappear 
completely at about four-fifths the distance from mouth to anterior end of stomach. 
In the single specimen sectioned a very peculiar gland (fig. 1, a) is present in the anterior por- 
tion of the esophageal region. It is situated in the mid-ventral line of the body, directly beneath the 
esophageal epithelium, and thus quite internal to the . body walls. A large and conspicuous duct 
(fig. 1, x ) filled with secretion passes through the body walls to the superficial integument, thus dis- 
charging the secretion from the gland on the mid-ventral surface of the body. The gland itself is 
composed of some 20 or more large clusters of gland cells, each cluster resembling one of the groups of 
Fig. 2. — Txniosoma univiltatum sp. nov. Transverse section through posterior end of 
esophageal region, showing section of esophagus (e) immediately anterior to its 
opening into dorsal wall of stomach, a short blind portion of which (sf) lies ventral 
to posterior end of esophagus; (rc) rhynehoccel; (In) lateral nerve. Other reference 
letters as in fig. 1, x 30. 
the cephalic glands (fig. 1, eg') which lie in the midst of the outer longitudinal muscular layer in the 
same region. The duct through which the secretion is discharged is, like the ducts from the cephalic 
glands, merely temporary, and exists only when filled with secretion. 
It is doubtful whether this gland occurs in all individuals of the species. It seems more probable 
that it is an abnormally developed cluster of cephalic glands which has pierced the underlying circular 
and inner longitudinal muscular layers, and has come to lie quite internal to the body walls. 
Alimentary canal.— Mouth and esophagus as in related species. At about midway between mouth 
and intestine proper the esophagus opens into the stomach, from which it is sharply demarcated both 
anatomically and histologically. In the single specimen sectioned the esophagus did not open directly 
into the anterior end of the stomach, but into the dorsal wall of the latter at some little distance from 
its anterior end. Thus a blind anterior pouch of the stomach (fig. 2, st) lies beneath the posterior end 
of the esophagus (e), and recalls the intestinal caecum of the Hoplonemertea. As commonly occurs in 
the Heteronemertea, the esophagus is much flattened dorso-ventrally, and is crescentic ip cross section. 
The epithelium of the ventral wall is several times as thick as that of the dorsal wall (fig. 2). The 
esophagus is somewhat diminished in size at its posterior end, although its opening into the dorsal 
wall of the stomach is quite large. 
