80 G. l^eyin—List of the Mollusca of , [No. 1, 



Ij reflected, produced and angled at base, outer margin rounded ; epidermis 

 dark olive-green ; under the lens a minute spiral sculpture can be detected. 

 Young specimens invariably show a sort of varix, formed probably at a 

 period when their growth is arrested by some cause ; this varix becoming 

 absorbed in adult specimens. Above 200 specimens were found at Yaylay- 

 maw. 



Long. max. 8f , min. 7t, diam. max. 6, min. 7f mil ; long, anfract. ult. 

 7 ; long, apert. 5^, diam. 3 mil. 



This species can easily be distinguished from the Indian S. cerameo- 

 poma and B. lutea : it is imperforate, has fewer whorls, a shorter and more 

 obtuse spire, the columellar margin is less acutely angled at base, the epi- 

 dermis green instead of brown. 



Maegarta, n. gen. 



This remarkable shell is very difficult to classify, owing to its great 

 analogy to two fresh-water genera, Paludina and Melania. I think, how- 

 ever, there is little doubt but that it will have eventually to rank as a sub- 

 genus of Faludina. Margarya, so named in honour of its discoverer, who 

 unfortunately shortly after was murdered near Momein by the Chinese, is 

 characterized by its produced, melania-like spire, composed of scalariform, 

 rapidly increasing whorls, with very distinct suture ; apex obtuse; sculptured 

 with j)rominent spiral ribs ; rimate (or umbilicate ?) ; margins of aperture 

 rounded, not continuous ; animal and operculum unknown. 



Maegarta melais'ioides, n. sp. 



Shell large, spire produced, melania-like, with very deeply excavated 

 suture, apex obtuse ; whorls six, convex, the first two flat and obtuse, the 

 third large and tumid (bigger in proportion than the fourth) ; the four last 

 whorls are girt with three nearly equally distant, raised, irregularly nodu- 

 lose keels, the middle one much the largest, having its nodules more deve- 

 loped and of a more or less compressedly transverse shape ; umbilicus very 

 small, almost entirely covered by the reflected columella ; aperture almost 

 circular, nearly as broad as high ; columella short, evenly rounded, moder- 

 ately reflected over the shallow umbilicus ; a slight callous between the 

 columella and outer lip ; remains of an epidermis distinctly traceable. 



A broken specimen of four whorls only, long. 67, diam 47 ; anfract. 

 ult. 44 ; apert. alt. 28i, lat. 27i mil. 



A perfect, but not quite adult, specimen (6 whorls) , long. 52, diam. 34 ; 

 anfract. ult. 35| ; apert. alt. 23 mil. 



Four dead and water-worn specimens of this exceedingly interesting 

 new form were picked up on the shores of Lake Tali in Yunnan by the late 

 Mr. Margary and were given by him to Dr. Anderson, who has expressed 



