SIR CHAELES 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 



PIG. 2. 



PIG. 3. 



PIG. 4. 



Tritoniella belli ANTERIOR PART OP BACK IN THREE SPECIMENS SHOWING THE VARYING 



ARRANGEMENT OF TUBERCLES. 



sheaths are directed either laterally or vertically, and their margins arc 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 oesophagus 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. 



