The Tanganyika problem; an account of the researches undertaken concerning the existence of marine animals in Central Africa . very long supra-intestinal connective, , exactly as it is in Cerithwm or Aporrhais. Viewedfrom the side, the cerebro-pedal and pleuro-pedal con-nectives are seen to be of considerable length, ratherlonger than the same structures in Voluta, but not so longas those in Nassopsis or in Strombtis. The pedal ganglionhas the bulbous form encountered in the true Cerithiidse,and in like manner there pass from the lower extremityof each pedal ganglion two predominent foot
The Tanganyika problem; an account of the researches undertaken concerning the existence of marine animals in Central Africa . very long supra-intestinal connective, , exactly as it is in Cerithwm or Aporrhais. Viewedfrom the side, the cerebro-pedal and pleuro-pedal con-nectives are seen to be of considerable length, ratherlonger than the same structures in Voluta, but not so longas those in Nassopsis or in Strombtis. The pedal ganglionhas the bulbous form encountered in the true Cerithiidse,and in like manner there pass from the lower extremityof each pedal ganglion two predominent foot nerves. THE TANGANYIKA PROBLEM. 243 The otocysts lie behind the pedal ganglia, and theotocyst nerves pass directly behind the cerebro-pedal andpleuro-pedal connectives to the cerebral ganglia on eachside. The otocysts are not large, and are round, asdistinguished from those of Nassopsis. The otoliths aresmall, rectangular or barrel-shaped, and numerous. The reproductive apparatus is very simple, and in bothsexes consists of a genital gland which occupies the uppersurface of the two last whorls of the animals body. This. Fig. 25.—Lingual dentition of Paramelania aamoiii. gland is put in connection with a large non-convolutedoviduct or vas deferens, as the case may be, by a numberof fine tubes ; and both ducts pass beneath the intestineand open just behind the anus in a large slit. The genital duct in both sexes is much enlarged withinthe mantle cavity, somewhat in the manner of the samestructure in the genus Typhobia. But in Bythoceras it isquite destitute of the singular organ which I described asan evertible penis in the male Typhobia* * Quart. Journ. Micr. Sci., Vol. 41, 1898, p. 191, loc. cit. 16* 244 THE TANGANYIKA PROBLEM. B. MINOR, MOORE (FIG. 24). During the second Tanganyika expedition a new speciesof Bythoceras was obtained, which has not yet been figuredor described, and to which I have given the above distinc-tive name (Fig. 24). This form is somewhat smallerthan
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