8 SIR CHARLES ELIOT. 
there is no tail whatever apart from the body. The genital orifices are 19 mm. and 
the anus 31 mm. from the anterior end; both lie just under the mantle margin. About 
5 mm. in front of the anus lie two openings, close together, but quite distinct and 
probably renal. 
The other specimens seemed to present the same configuration in a more or less 
damaged condition. Though they are larger, the dorsal margin is never more than 
5-8 mm. in breadth, and often quite narrow. Only a few processes (3-7) remain 
on each side. Some of them are rather larger than in A, and though they show no 
traces of having been arborescent, or even simply pinnate, they bear one or two deep 
indentations. The tubercles on the edge of the oral veil are very indistinct. The 
ridges and tubercles on the back differ considerably in the different specimens, and 
seem to indicate a real variability. Traces of the T-shaped lateral ridge on the right 
are generally but not always present, and between the rhinophores there are from one 
to three tubercles of very varying shape and size (Figs. 2-4). The rhinophore 
Fie. 2. Fig. 3. Fia. 4, 
Tritowiella belli—ANTERIOR Part OF BACK IN THREE SPECIMENS SHOWING THE VARYING 
ARRANGEMENT OF TUBERCLES. 
sheaths are directed either laterally or vertically, and their margins are generally 
turned outwards. 
The body-walls are thick, the dorsal integuments much thicker posteriorly than in 
the centre of the back. The body cavity is only about 30 mm. long, the solid tail 
measuring 18°5 mm. The pericardium is not visible externally, and lies somewhat to 
the right of the median dorsal line. The central nervous system is as in Tritonia, but 
no eyes were discovered. The ganglia are very distinctly granulate and yellowish. 
The pedal ganglia are round, the cerebro-pleural larger, but without any sign of a 
division into two parts. The elongate, elliptical buccal ganglia are applied closely to 
the under side of the cesophagus at some distance from one another, and the small 
round gastro-cesophageal ganglia are united to them by long connectives. 
The buccal mass is of the Tritonia type, and presents no important differences in 
any of the specimens. The jaws are strong (Fig. 5), very convex, and present a 
roughly circular appearance (with a diameter of about 7-5 mm.) as they lie together. 
