8 



SIR CHARLES ELIOT. 



there is no tail wliatevcr 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. Aljout 

 5 mm. in front of the anus lie two openings, close together, but cjuite 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 ax'e 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 rhinophorc 



Fig. 3. 



Pig. 4. 



Tritoniella belli — Anterior Part of Back in three specimens showing the varying 



ARRANGEMENT OP 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 l)ody cavity is only aljout 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, l)ut 

 no eyes were discovered. The ganglia are very distinctly granulate and yellowish. 

 The pedal ganglia are round, the cerebro-pleural larger, Imt without any sign of a 

 division into two parts. The elongate, elliptical l)uccal 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. 



