196 
ON A COLLECTION OF NON-MARINE SHELLS, FORMED BY 
MR. J. J. WALKER, IN THE NEW HEBRIDES. 
By E. R. Syxes, B.A., F.L.S., ete. 
Read 13th June, 1902. 
Tue shells noticed in the following pages were collected by Mr. J. J. 
Walker during the cruise of H.M.S. ‘ Ringarooma”’ in the New 
Hebrides between June and October, 1900. The collection is of 
interest, not only on account of the three new forms discovered, 
but also for the very careful localization of the species, which forms 
a useful contribution to our knowledge of the fauna of those islands. 
All the specimens have been kindly presented by Mr. Walker to the 
British Museum. 
1. Raryea rapa (Pfr.). 
Hab.—Port Fila, Efate. 
2. Microcystis eurruta (Gould). 
Hab.—Port Fila, Efate. 
I consider that Hyalina Layardi, Thomson (Proc. Zool. Soe., 1885, 
p- 25), is only a synonym for this well-known species. 
3. TrocHomMoRPHA RUBENS, Hartman. 
Hab.—Terebu and Renée River, Espiritu Santo; Havannah 
Harbour, Efate. 
4. TrochomoreHa convexa, Hartman. 
Hab.—Terebu and Renée River, Espiritu Santo. 
5. TrocHoMorPHA, sp. 
Hab.—Ravenga, Vanua Lava; Renée River, Espiritu Santo. 
A puzzling form, approaching 7. approximata. 
6. Denprorrocnus Layarpr (Hartman). 
Hab.—Renée River, Espiritu Santo. 
7. Denprorrocuus Eva (Pfeiffer). 
Hab.—Port Fila, Efate. 
8. DrnDROTROCHUS STRAMINEDS, n.sp. (Fig. I.) 
Shell belonging to the group of D. Zva, but more depressed, much 
smaller and thinner, being almost translucent, and of a pale yellowish- 
white colour, with half a whorl less. The surface is finely malleated, 
