18 PROCEEDINGS OF THE ACADEMY OP [1879. 



Patula Rurutuensis, sp. nov. 



Shell umbilicate, discoid, thin, translucent, .yellowish-horn color, 

 the spire tessellated, and the last whorl with radiating flexuous 

 fuscous stripes ; radiately ribbed with small thin flexuous costae, 

 and decussated with microscopical raised lines; spire depressly con- 

 vex ; suture sub-canaliculate; whorls 5, convex, narrow, slightly 

 turgid near the suture; slowty and regularly increasing, the last 

 not descending in front, sub-angular on the periphery; umbilicus 

 deep, about one-fourth the major diameter of the shell; aperture 

 somewhat oblique, depressly lunate ; parietal region with a small 

 revolving lamina on the upper third of the wall ; peristome acute, 

 straight, with remote margins. 



Major diameter 3|, height 2 mill. 



The fine spiral stria?, thin ribs, single parietal lamina, and de- 

 pressed sub-angular body whorl are its most prominent characters, 

 and will readily distinguish it from any of the south Polynesian 

 species. 



Pitys De Gagei, sp. nov. 



Shell umbilicate, sub-discoid, thin, translucent, corneous or lute- 

 ous, horn color, spire more or less distinctly tessellated with chest- 

 nut-brown, and the last whorl radiately strigate with the same hue, 

 the stripes sometimes flexuous, and the base either unicolor or 

 adorned with stripes; sculptureconsistingof fine, closely-set, radiat- 

 ing, slightl}' arcuate, thin, costulate strhe, smaller and more crowded 

 beneath; spire convex, apex planulate; suture canaliculate ; whorls 

 6, convex, narrow, swollen next the suture, slowly and regularly 

 increasing, the last not deflected in front, slightly depressed, and 

 somewhat tumid ; base moderately convex, with a small but deep 

 umbilicus; aperture slightly oblique, narrow, lunate; the palate 

 with five, and the parietal wall with three revolving lamina; peris- 

 tome acute, straight, margins remote. 



Major diameter 3, height 1^ mill. 



Closely allied to P. llaupiensis. but may be distinguished by 

 its coarser, rib like stria?, more oblique aperture, smaller umbilicus, 

 and more depressed body whorl. 



Partula hyalina, Broderip. 



Partulahyalina, Broderip, Proc. Zool. Soc. 1833, p. 32. 

 Bulinus hyalinus, Sowerby, Conch. 111. fig. 9. 

 Bulimu* hyalinus, Pfeiffer, Mon. Hel. vol. II. p, 67. 

 Purtulus hyalinus, Beck, Ind. p. 47. 



