452 SUCCIXEID^E. 



rugosa, nitide fulvescente ; spira brevissima ; anfr. 2J, ultimo 

 inflate; apertura ovali, margiue sinistro valde arcuato ; perist. 

 simplice, membranaceo. 



"Long. 14, diam. 10 mill." (Pfeiffer.) 



Hob. India: Pondicherri (Guerin). 



Only known from the description and figure. I have not seen 

 any shells which can be referred to this species. 



448. Succinea semiserica, Gould. \ 



Succinea semiserica, Gould, Proc. Boston Soc. Nat. Hist, ii, 1846, 

 p. 100; Pfeiffer, Mon. Helic. Yiv. iii, 1853, p. 10; iv, 1859, 

 p. 805 ; Gould, Otia Conch. 1862, p. 199 ; Hanley & Theobald, 

 Conch. Ind. 1874, pi. 67, figs. 2, 3 ; Nevill, Hand List, i, 1878, 

 p. 212. 



Succinea semisericea, Reeve, Conch. Icon, xviii, 1872, Succinea, 

 pi. 2, fig. 9. 



Succinea (Brachyspira) semiserica, Pfeiffer & Clessin. Nomencl. 

 Helic. Viv. 1881, p. 410. 



Original description : " Testa fragilis, ovalis, a tergo depressa, 

 postice straminea, antice albido-sericea, longitudinaliter plicoso- 

 striata ; anfr. 2|, ultimo maximo ; apertura ovata, patula, facie m 

 inferiorum fere adequante. 



"Long, [ = 12-75 mm.]; lat. r 3 7 [=7'6 mm.]; alt. fo poll. 

 [=3-8 mm.]." (Gould.) 



Hob. Burma : Tavoy (Gould) ; Eangoon, Moulmain (Stoliczka) ; 

 Chittagong (Raban) ; Pegu (Theobald); Mergui (Mus. Brit.). 



" Its shape is like S. tigrina, Fer., and it is well characterized 

 by the peculiar silky-white or pearly surface of the anterior half 

 of the shell." (Gould.) 



Nevill considered /S. plicata, Blanford, and perhaps S. baconi, 

 Pfeiffer, cospecific with semiserica. The three forms are, however, 

 quite distinct. The present species has an extremely short spire 

 and is finely, distantly ribbed. Owing to a deficiency of calcareous 

 matter the shell is very brittle. This applies especially to some 

 shells from Rangoon, in the Theobald collection, which are 

 labelled S. rangoonensis a name never published but which 

 pertain to the present species ; they are extremely thin, almost 

 transparent, and of a fuscous corneous colour. Their dimensions 

 exceed those given by Gould, i.e. 15 x 9 x 3. Three specimens 

 from Pegu, in the Theobald collection, are pale greenish corneous. 

 The Cuming collection comprises shells from Tavoy measuring 

 14x8x3*5 mm., which therefore also exceed Gould's type in 

 size ; on the other hand, there are specimens from Mergui in the 

 general collection of the British Museum which attain a size only 

 of 8x4-5x2 mm. 



449. Succinea baconi, Pfeiffer. 



Succinea baconi, Pfeiffer, P. Z. S. 1854, p. 298 ; ibid., Mon. Helic. 

 Viv. iv, 1859, p. 804 ; Reeve, Conch. Icon, xviii, 1872, Succinea, 



