AMPULLAEID^. 899 



A few specimens were foimcl at Myadoung ; they agree perfectly witli Reeve's 

 fig. 156 B (Jf. sjnmilosa, Lamk.) 



YamWj—AMPUIZjmD^. 

 Genus Ampullaria, Lamarck. 

 Ampullaeia theobaldi, Hani. 



Ampullaria theolaldi, Hanley, Con. Indicaj pi. 115, fig. 2; Nevill, I. c, p. -37. 

 f Anipnllaria maura, Hy., var. Con. Icon., fig. 57. 



Unfortunately, none of the 16 specimens collected by Dr. Anderson at Bhamo 

 are quite full-grown, the outer lip in all of them being thin and sharp ; in the de- 

 pression of the spire they agree with Beeve's figure of A. maura, as well as the 

 typical figiu'e of A. theohalcU ; the umbilicus is open, agreeing exactly with the 

 latter figure ; the coloration and shape of the aperture are also the same ; I think 

 it very doiibtful, however, if it can be separated as a distinct species from the com- 

 mon Assam form, from which it only seems to differ by its larger size, less produced 

 spire, shghtly more open umbilicus, and in the coloration being a shade more vivid ; 

 in the latter two respects, however, some few Assam specimens approximate most 

 closely. 



ACEPHALA. 



Yamily—UmONIBM 



Genus Unio, Betz. 



TJnio marginalis, Lamk., var. savadiensis, Nevill. 



Unio marginalis, Lamk., Anim. s. Vert., t. vi, 18.35, p. 544; Con. Indica, pi. ix, fig. 6 (sp. juv.) 



Unio marginalis, var. savadiensis, Nevill, I. c, p. 37. 



This variety is abundant at Sawady in the Thengleng stream, also at Bhamo 

 and at Shuaygoomyo; fom* young specimens found at Myadoung probably also 

 belong to this form. The nearest figured variety is obesa, Hani., ' Con. Indica,' pi. 44, 

 fig. 7, from the Irawady ; var. savadiensis is of a more ovate shape, of a slightly 

 thinner texture, the nacre is of a light salmon or cream-colour, instead of the ordi- 

 nary bluish- white tinge characteristic of var. ohesa, the difference of colour in the 

 nacre is constant both in young and old shells ; the lateral teeth are more convex, 

 the cardinal ones a little less strongly developed ; young specimens of both varieties 

 are prominently wiaged, as in var. lamellatus} Externally, young specimens are of 

 a gamboge-yellow colour, tinged with bright green on the wing. 



Long. max. 113, lat. max. 68 mm. 



' Con. Indica, pi. xliv, fig. 7. 



