1887.] MOLLUSKS OF THE VITI ISLANDS. 165 



which is unexplored, will undoubtedly produce many species not 

 found in other parts of the archipelago. 



The genus Succinea, so widely diffused throughout the Pacific 

 islands, has not been discovered in these islands. 



The earliest known Vitian endemic land-shells are Bulimus mallea~ 

 tus, B. fulffuratus, and Helix nouleti, all described in the ' Revue 

 Zoologique ' in 1842, the two former by Dr. Jay, and the latter by 

 Le Guillou. In 1845, Philippi published Helix pfeifferi, and Mr. 

 Hinds described Pythia pollex. In 1846 and 1847, Dr. Gould 

 added several new species, all discovered by the U. S. Exploring 

 Expedition. In 1855 Dr. Pfeiffer described Helix ludersi; and six 

 years later Dr. Dohrn added the beautiful Bulimus seemanni to the 

 list of endemic species. In 1865, Prof. Mousson published, in the 

 'Journal de Conchyliologie,' a complete list of the Viti land and 

 freshwater shells, based on the collections made by Dr. Graffe and 

 added several new species to the 16 peculiar to the group. In 1870 

 Mousson's second paper appeared in the same Journal, and he de- 

 scribed 26 new species, all collected by Dr. Graffe. In the meantime 

 several new species were published by H. Adams, Crosse, Angas, 

 and Semper. 



In the ' American Journal of Concho] ogy ' for 1871, and in the 

 ' Proceedings of the Academy of Natural Sciences of Philadelphia ' 

 for 1873, the writer published descriptions and figures of 20 new 

 species, all personally collected. The latest discovery, so far as I 

 can ascertain, is six new minute species collected by Mr. Liardet, 

 which were published and figured with their animals in the ' Proceed- 

 ings ' of the Zoological Society for 1876. 



Out of 146 species now recorded 85 are peculiar to the group. The 

 146 species are embraced in 32 genera, 11 of which are operculated. 



Genus Helicarion, Ferussac. 



1. Helicarion vitrinina. 



Naninal vitrinina, Liardet, Proc. Zool. Soc. 1876, p. 100, pi. 5. 

 figs. 2, 2a. 



" Shell yellow, thin, translucent, perforated, discoidal ; whorls 4^, 

 last subangulated, the others slightly convex ; beneath shining and 

 well rounded ; aperture slightly oblique, lunate ; suture marginate ; 

 peristome thin ; columella slightly expanded over the perforation. 

 Animal black, with mantle covering two thirds of the shell, which it 

 cannot enter at first." 



" Found in moist situations under logs, in this respect resembling 

 Vitrina." {Liardet.) 



This species, which is unknown to me, was found at Taviuni Island. 



2. Helicarion ramsayi. 



Nanina 1 ramsayi, Liardet, Proc. Zool. Soc. 1876, p. 100, pi. 5. 

 fig. 3. 



" Shell similar to N, ? vitrinina. When the animal is out I can 

 detect no difference. 



