AMPULLAEIDiE, 899 



A few specimens were found at Myadoung ; they agree perfectly with Eeeve's 

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



¥ixm\lj—AMPUZZABIDM 

 Genus Ampullaria, Lamarck. 

 Amptjllaria theobaldi, Hani. 



AmpuUaria theohaldi, Hanley, Con. Indica^ pi. 115, fig. 2; Nevill, I. c, p. 37. 

 / AmpuUaria maura, Rv., var. Con. Icon., %. 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 figure of A. tlieobaldi ; 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 doubtful, 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. 



Family— UNION IB^. 



Genus Unio, Betz. 



Unio maeginalis, Lamk., var. savadiensis, Nevill. 



Unio marginalis, Lamk., Anim. s. Vert., t. vi, 1835, 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 Bham6 

 and at Shuaygoomyo; four young specimens found at Myadoung probably also 

 belong to this form. The nearest figured variety is ohesa, 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 winged, 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. 



