REPORT OR THE NUDIBRANCHIATA. 
75 
The teeth are clear yellow coloured. The length of the innermost of them measures about 
‘04 mm., increasing gradually to T7 mm., then decreasing towards the exterior, the four 
outermost measuring '09-'08, '075 or '05 mm. The innermost teeth have from one to 
two denticulations on the inner side of the hook, and about four upon the outer side 
(fig. 27, bb). Throughout the row of teeth the length of the hook gradually increased, but 
decreased at the outermost portion ; the length of the basal portion, on the contrary, only 
increased very little, and decreased again in the outermost portion of the row. All the 
teeth were denticulated along the outer margin almost as far as the end of the hook (PL III. 
fig. 29 ; PI. IV. fig. 2) ; the smooth bent termination had quite disappeared in the outer- 
most one to three teeth (figs. 28, 29). The number of denticulations was usually from 
seven to nine, sometimes eleven to twelve ; on the innermost five to eight teeth they were 
fewer in number, mostly four or five ; also in the outermost five or six were commonly 
seen ; there were, however, several of the outermost teeth with only eleven or twelve of 
the finest denticulations (fig. 29, a). There were also several quite smooth teeth. 
The salivary glands are of considerable extent, and whitish in colour, about 12 mm. 
long by '3-'5 mm. in thickness ; they pass backwards from the bulbus beneath the 
anterior genital mass, and are attached to the liver ; they run side by side in the middle 
line, and frequently wind round each other. The efferent ducts are short. 
The oesophagus is about 2 '5 mm. broad by 8 mm. in length, on the inner surface are 
strong longitudinal folds ; it opens into the cavity of the liver by a wide circular opening, 
which here appears to act as a stomach ; it was filled with the debris of food. Be- 
hind the middle of the upper left hand wall is the round opening into the intestine, which 
in its anterior part is about 9 '5 mm. long ; it increases in width posteriorly up to 2 '5 mm., 
and then narrows to about 2 mm. ; the posterior half has a length of about 15 mm., by 
a diameter of 1'2 mm. Its interior has numerous fine longitudinal folds. The contents 
of the intestinal tract were indistinguishable animal remains. 
The liver is 9 mm. long by 7 '5 mm. in breadth, and 6 '5 mm. in height; the anterior 
portion is broad, obliquely cut off behind and on the right, with a deep median cleft for 
the oesophagus ; the somewhat narrower hinder end is rounded ; on the left of the 
anterior half of the upper side is a broad furrow for that portion of the intestine which 
runs forward ; on the right hand is a narrower furrow for the portion directed backwards ; 
the colour of the (upper part of the liver) is brownish-grey ; its interior yellowish-white. 
The gall-bladder is large and sac-like, 2 '5 mm. in diameter; lying in front of the base of 
the intestine and beneath it, opening by a short duct. 
The pericardium is large. The chamber of the heart (PI, IV. fig. 3, b) about 2 mm. long. 
The blood glands cover the central nervous system ; they are whitish, very flattened, 
irregularly-oval, and lobulate on the margin ; the anterior is 3 mm. thick, the hinder 4 mm. 
The urinary chamber (fig. 3) forms a deep cleft, with a round lumen, with numerous thicker 
or thinner ridges and partition walls at the sides, which are visible through the thin upper 
