536 MR. E. A. SMITH ON THE TERRESTRIAL [DcC. 4, 



Several specimens. Closely allied to A. boutoni, Desj., from 

 which it differs in the distinct interparietal shield. 



Lygosoma nativitatis, Blgr. 



This species was established upon a single tailless specimen. 



Eight specimens were secured by Mr. Lister. The tail, when 



intact, is two thirds of the total length. Young with the dorsal 

 scales strongly quiuquecarinate. 



7. On the Terrestrial Mollusks of Christmas Island. 

 By Edgar A. Smith, F.Z.S. 



[Eeceived October 15, 1888.] 



The only species of Land-shells at present recorded from Christmas 

 Island are the two Succinece and the two forms of Melampus obtained 

 by the ofBcers of H.M.S. ' Flying-Fish,' and recorded in the ' Pro- 

 ceedings ' of this Society, 1887, pp. 517-518 ^ 



Only one of these, Succinea solidula, Pfr., was obtained by Mr. 

 Lister; who, however, succeeded in discovering seven additional 

 species, four of which appear to be new to science. 



The following is a list of all the known species : — 



1. Ariophanta (Microcystis) nokmani, sp. n. 



2. Ariophanta (Microcystis) mabel«, sp. n. 



3. Ariophanta (Microcystis) mildredjE, sp. n. 



4. Succinea solidula, Pfeiffer. 

 a9j, 5. Succinea solitaria. Smith. 



6. Succinea listeri, sp. n. 



7- Pythia scARABiEus, Linn. 



8 Melampus luteus, Quoy & Gaimard. 

 - 9. Melampus fasciatus, Deshayes. 

 10. Truncatella valida, Pfeiffer. 



] I . Leptopoma mouhoti, Pfeiffer, var. 



The Pythia, the two Melampi, and the Truncatella are all 

 widely ranging species, occurring in the Malay Archipelago and 

 Polynesia. The Leptopoma, if I am right in its identification, occurs 

 also in Camboja ; and the remaining species, although at present 

 known only from Christmas Island, may also have a wide distribution, 

 as allied forms exist in the Philippines, Moluccas, &c. 



^ I take this opportunity of altering the name of the new species of LUtorina 

 described P. Z. S. 1887, p. 519. Eeeve having already employed the name 

 grano-costata, T propose to caU the species from Christmas Island L. insularis. 



