40 G. NeyiW— List of tie Mollusca of [No. 1, 



Very abundant at Myadoung, Irawady Second Defile, Shuaygoomyo, 

 Yaylaymaw, and Bhamo. It varies considerably in being more or less 

 rugose in sculpture. 



Long. max. 52, lat. max. 29, crass. 24 mil. 



Unio Andeesois^iana, n. sp. 



This species was found at Myadoung in tolerable abundance, together 

 with JJ. Bonneaudi and several other species ; two specimens were also obtain- 

 ed on the First Expedition at Shienpagah. It is next allied to TI. pacTiy so- 

 ma, Bens., and to some of the varieties of Z7. c<sruleus, Lea. It is easily 

 distinguished from U. JSonneaudi by its more irregular shape, thinner texture 

 by the acute angulation, greater production posteriorly, and by the 

 more developed sculpture ; a constant character also is the pink colour of 

 the nacre, which in TI. Boniieaudi is bluish white, this is equally distinct 

 and characteristic in young as in old specimens. 



Type from Myadoung, long. 32, lat. 15i, crass, llf mil. 



Specimen of TI. Bonneaudi from Myadoung, long. 31, lat. 18, crass. 13 

 mil. 



CoEEicuLA Lamaeckiais-a, Prime. 

 CorUcula LamarcTciana, Prime, Ann. Lye. N. York, 1867 (Mt. Laos, Cambodia). 



Specimens obtained at Hotha and Momein (5,500 feet) in Yunnan, and 

 also at Mandalay, agree exactly with Prime's original figure. Major God- 

 win-Austen also found a small form of this well-marked species at Manipiir, 

 in the Kuchai stream. 



Long. 28|-, lat. 20^, crass. 13 mil. 



COEBICULA YuNIfANENSIS, n. Sp. 



Medium-sized specimens from Yaylaymaw agree fairly with Prime's 

 figure and description of C. Linneana, (Ann. Lye. N". York, 1867, Cambodia), 

 the principal difference being the less truncate anterior side. Shell large, 

 thick, transverse, inequilateral, compressed, rather abruptly tumid towards 

 the umbones ; anteriorly moderately produced and rounded, ^posteriorly j^ro- 

 duced and truncate (exactly as in Prime's figure of G. Linneana) ; lateral 

 teeth curved, the anterior a little more so than the posterior ; no lunule ; 

 epidermis dark brown, striae regular and close ; interior violet, of a darker 

 shade near the margin. This species is more inequilateral, more tumid near 

 the umbones, and more regularly sulcated than G. 3Iullerimia, Prime (Joe. 

 cit.), from China, which, however, it also closely resembles. 



Type from Manwyne in Yunnan (4,000 feet) : long. 39, lat. 33 mil. 



Yaylaymaw (all young) : long. 21i, lat. 17, crass. Hi mil. 



