400 Mr. W. E. Collinge on some 



similar cavities, only much smaller, the most anterior one 

 opening into the vestibule (PI. VII. fig. 9). 



The retractor muscle is inserted just below the distal 

 division (PI. VII. fig. 9, r.m.), and is conspicuous owlno^ to 

 the fact that the muscle-fibres radiate and form a disk-like 

 point of insertion. The free oviduct is produced into a pouch- 

 like cavity on the left side (looked at dorsally), the external 

 wall of which is minutely pitted, more so perhaps ventrally 

 than dorsally. At the point where the prostatic portion of 

 the common duct joins with the vas deferens the terminal 

 portion of the former is free, though not to such an extent in 

 the specimens I have dissected as figured by Simroth (.^, 

 t. viii. fig. 13). The dart-sac opens into the vestibule on the 

 right side ; it passes backwards beneath the penis and vagina, 

 and making a sinuous curve, lies to the right of the terminal 

 ducts. Its structure is very similar to that described below 

 for M.javanica. The dart (PI. VII. fig. 10), which is about 

 2 millim. long, is a slender slightly curved rod with a solid 

 calcareous head. 



5. Microparmarionjavanica^sp.n. (PI. VIII. figs. 11-19.) 



Hab. Geda. Three specimens. Type in coll. of W.E. C 

 Animal (PI. VIII. figs. 11-13) purply brown, darker poste- 

 riorly, sides of head lighter. Mantle-lobes same colour but 

 darker, spotted with small black spots; whole of mantle 

 (excepting portion bordering shell) and the postero-lateral 

 portions of the body are studded with minute wart- like pro- 

 tuberances Peripodial groove distinct. Kugse large. Foot- 

 fringe greyish brown, with faintly coloured lineoles. Foot- 

 sole divided into median and lateral planes, former yellow in 

 colour, latter purply blue. Keel prominent, yellowish brown. 

 Caudal mucous pore a vertical slit, not extending to the foot- 



Length (in alcohol) 25 millim. 



Shell (PI. VIII. figs. 14 and 15) oval in form, solid, amber- 

 colour, tlie lines of growth strongly and regularly marked ; 

 apex distinct. 



Major diameter 10 millim., minor diameter 6'5. 



The mantle in this species is not unlike that in M. Austeni\ 

 Simr. ; a transverse section through the same showed the 

 following structure : — The epidermal cells in certain areas are 

 covered with a thick yellowish layer of a gum-like substance ; 

 these regions are raised up, forming in the section little 

 hillocks ; these in the living animal have the appearance of 

 wart-like bodies. 



