226 
appears at the periphery and the other between it and the sumrnit. The space bet- 
ween the peripheral keel and the next one is a little narrower tlian the space bet- 
ween the median and posterior keel, while the space between the summit and the 
posterior keel is considerably wider still. The space between the summit and the 
posterior keel is moderately rounded and forms the shoulder of the whorl. The 
spaces between the other keels are flattened. The greatest convexity of the whorls 
is marked by the median keel. Periphery of the last whorl angulated. Base mo- 
derately long, strongly arched. The entire surface of the spire and base is marked 
by rather strongly expressed incremental lines and many closely placed microscopic 
spiral lirations. Apertare large, subcircular, reddish brown within; outer lip thin, 
rendered slightly angular by the keels; columella slender, concave, somewhat reflec- 
ted over the umbilical area; parietal wall covered with a moderately thick dark 
colored callus. Operculum thin, yellowish, with decidedly eccentric nucleus, marked 
by many lines of growth.“ — Bartsch. 
Aufenthalt im See von Lanao auf der Philippineninsel Mindanao. — Abbildung 
und Beschreibung nach Bartsch. — Offenbar eine Seeform der Vivipara costata 
Quoy. 
116. Vivipara mainitensis Bartsch. 
Tat. 45. Fig. 7 — 9. 
Testa exumbilicata, ovato-conica, solida sed haud crassa, haud nitens, irregulariter 
grosseque oblique striata et costis spirali'ous rudibus planis sulcisque angustis undique sculpta, uni- 
color saturate fusca. Spira conica. apice vel eroso vel incrassato; sutura impressa. Anfractus 
6 (?) convexi, inferi infra suturam tabulati et angulati, ultimus maguus, convexus, nisi prope 
umbilicum undique costis rudibus, peripherica saepe multo latiore, cinctus, antice haud vel 
vix descendens. Apertura sat obliqua, ovata, faucibus fuscescentibus et fasciolis, sulcis ex- 
ternis nec costis respondentibus ornatis; peristoma tenue, callo tenui subcontinuum, margine 
externo ad sulcos crenulato, columellari arcuato, albo-calloso, appresso, supra intrante. 
Alt. 38, diam. 30, alt. apert. 20, diam. 16 mm. 
Vivipara mainitensis Bartsch, in: Pr. U. St. Nat. Mus. 1907, vol. 32 p. 148 
t. 10 f. 9—11. 
Vivipara multisulcata Moellendorff in sched. — Sarasin, Celebes p. 61. 
Schale völlig entnabelt, eikegelförmig, fest, aber nicht besonders dickwandig, 
glanzlos, unregelmässig und grob schräg gestreift, bis auf einen kleinen Raum um 
