1895.] NEW MOLLUSCS FEOM BORNEO. 247 



form of the teeth. The lingual ribbon was extracted in a very 

 perfect state, showing one hundred ro^s of teeth arranged thus 



90—16—1—16—90 

 106—1—106. 



Generative Oir/ans (figs. 32-35). — The vagina is larger than in 

 M. pollonerai, as is also the sessile receptaculum seminis, which 

 is somewhat pyriform in shape. The penis opens into the ves- 

 tibule as a comparatively narrow tube, but as it approaches the 

 vas deferens it dilates into a large sac-like bead, from which the 

 flagellum arises ; the latter organ is looped back upon itself and 

 of the same diameter througbout, terminating blindly. In one 

 specimen it was somewhat produced, as shown in figure 34. The 

 vas deferens leaves the head of the penis as a wide tube, becoming 

 narrower in the middle and dilating again previous to entering 

 into the prostate. The common duct is similar to that in M.jpollo- 

 nerai, only not so richly convoluted ; it differs also in being much 

 straighter and not coiled upon itself as in M. poUonerai. The 

 albumen-gland is small and ovoid. The hermaphrodite gland is 

 small and triangular in shape, with a thin convoluted duct. 



2. Affinities. 



The nearest species as regards internal anatomy to either of 

 these two species of Microparm avion is Parmarion piipillaris, 

 Humb., from Java, notwithstanding the fact that the shell is very 

 rudimentary. It is figured by von Martens (5. pi. xii. fig. 3), who 

 localizes Parmarion to this part of the world. The generative 

 organs are figured by Semper (6), whose figure we have reproduced 

 for purposes of comparison. The form of the penis and recepta- 

 culum seminis and amatorial organ are very difEerent from those 

 in either of the species here described. The dart is cut off like a 

 pen near the point (fig. 37). In the jaw and lingual ribbon there 

 is a complete analogy. 



A comparison, however, of all the characters with those of 

 Girasia of India and Burma shows that these Malayan forms differ 

 sufficiently to constitute them a distinct race ; and if we could 

 only obtain more material, in which other characters, such as the 

 spermatophore, might be examined, a still greater divergence would, 

 we think, be found associated with the small sessile receptaculum 

 seminis. 



Simroth (7), in his latest paper on these slug-like land-molluscs, 

 veiy rightly divides the genus into two, viz., Parmarion and a new 

 genus Microparmarion, distinguishing this latter by the sessile 

 receptaculum seminis and solid sagitta amatoria. It will be seen 

 that among the Javan forms figured by him on plates vii. and viii., 

 Microparmarion struhelli agrees in some respects with M. simrothi, 

 particularly in the calc-sac of the male organ and in the hard 

 calcareous dai-t rising from the funnel-shaped base, and externally 

 by the black lines on the dorsum and region of the head. In 



