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Show 1897.] NEW SLUGS FROM BORNEO. 781 an der Unterseite noch einen Best von Gevunde. Der Liebespfeil hat eine solide Kalkspitze. Der Penis ist ein diinner, in der geraden Scheide mehrfach zusammengekriimmter Schlauch, so dass das innere L u m e n dem iiusseren Umfange durchaus unahnlich ist. Beceptaculum sitzend." After a careful perusal of the literature on these and allied genera, and a comparison of Simroth's figures with the material from Borneo, I fail to see where the line can be drawn between Parmarion and Micropannarion. In both genera the shell is variable. In the latter genus Simroth says the dart has a solid calcareous point, whereas in the former he describes it as being open at the end in the form of an oblique slit. In Parmarion intermedium, the dart Is solid, non-calcareous, and there Is no opening of any description. In Parmarion he describes the penis as being long and straight, whereas in Mlcroparmarlon it is thinner and constricted; but I would point out that inMlcroparmarlonpolloneral, Cllge. & G.-A.1, there is a long and straight penis. The value of the sessile receptaculum seminis is lessened by the condition which obtains in P. pupillaris, Humb., and more so by that in P. intermedium. From the above facts it will be seen that tbe two genera, as well as allied genera, are as yet but ill-defined, and that satisfactory characters are yet wanting to define the precise limits of each genus. I therefore sincerely hope that further material may be forthcoming from Borneo and elsewhere whereby sound generic characters may be established for these very interesting molluscs. EXPLANATION OF PLATE XLIV. Fig. 1. Parmarion everetti, n. sp. View from right side, X 2 (p. 778). 2. Caudal mucous pore, X 3 (p. 778). 3. Generative organs, X 3 (pp. 779, 780). 4. Parts of the generative organs of Parmarion martensi, Simr. (after Simroth), (p. 779). 5. Parmarion intermedium, n. sp. View from right side, X '5 (p. 779). 6. Visceral mass, showing spiral fold, X 2 (p. 779). 7. Caudal mucous pore, X 3 (p. 779). 8. Generative organs, X 2 (p. 780). 9. Enlarged figure of Denis, showing ventral side (p. 780). 10. Dart, X 3 (p. 780)! 11. Eeceptaculum seminis and duct, X 5'5 (p. 780). Letteriny. alb.gl. Albumen gland. d.s. Dart-sac. h.d. Hermaphrodite duct. h.gl. Hermaphrodite gland. m. Muscles attached to vagina. ov. Oviduct. p. Penie. pr. Prostate. r.m. Retractor muscle. r.d. Receptacular duct. r.s. Receptaculum seminis. v. Vestibule. v.d. Vas deferens. vg. Vagina. 1 Proc. Zool. Soc. 1895, pl. xiii. figs. 22-23. PROC. ZOOL. Soc-1897, No. LI. 51 |
