﻿624 ME. L. V. DALTON ON THE [NoV. I908, 



Family Cxeenid-^. 

 Batissa KODOinsrGEsrsis, Noetling. (PI. LVI, figs. 1 & 2.) 



1901. Cyrena (Batissa) kodoungensis, Noetling, Pal. Ind. n. s. vol. i, no. 3, p. 183 

 & pi. xi, fig. 1. 



Description. — The shell is large and orbicular. Anterior 

 margin round and short, passing gradually into the curved ventral 

 margin, wliich is straight posteriorly and is met by the posterior 

 margin at a right angle, the corner of which is rounded. The 

 posterior margin is straight, and passes over a rounded obtuse angle 

 into the curved cardinal margin. 



Beaks thick, incurved, prosogjTous ; ligament strong ; hinge 

 powerful. Three cardinals in each valve — the anterior shortest, 

 inclined backwards, the others inclined forwards. The middle one 

 is the strongest in the left valve, the posterior being very long but 

 thin ; in the right, the posterior cardinal is longest and thickest. 

 Two fairly short anterior laterals in the right valve ; posterior 

 laterals at some distance from the cardinals, not perfectly known ; 

 corresponding sockets in the left valve. 



The shell is very thick, covered with coarse irregular growth- 

 striations. 



Dimensions in Millimetres (two specimens). 

 Lejigth. Height, Thickness. 



100 96 60 (?) 



90 80 50 



Remarks. — Though from a distant locality and oE greater size, 

 these specimens, which are of brackish or freshwater origin, seem 

 to belong to the same species as the fragments from Yenangyoung 

 described by Dr. jS'oetling, which were apparently collected from 

 the same spot as those brought to England by J. Crawfurd in 

 1828, and referred to by Buckland as ' Cyrena.' ^ The shells come 

 from an horizon, according to Dr. Ncetling, high up in the Pegu 

 Group ; but, from my own observations, I should say that the bed 

 containing them may perhaps be more properly included in the 

 Irawadi Series. The present specimens were brought to me by 

 natives, and their horizon is not definitely known (see p. 615). 

 The size is much greater than that of Batissa Crawfurdi, Noetling, 

 from the Yenangyoung locality, and the species differ in important 

 points. The living B. insignis, Deshayes,^ from the Philippines, 

 appears to be a near relative, although the size of this is apparently 

 not so great, nor is the shell so robust ; but the hinge and the shape 

 of the shell are very similar. B. producta, Deshayes (loc. cit.), from 

 the same locality, is more rounded posteriorly, but otherwise much 

 resembles this species. 



Locality. — Letpan choung, 10 miles east of Sawmyo (Pakokku 

 district). 



^ Trans. Geol. See. ser. 2, vol. ii (1828) pt. iii, p. 386. 

 2 Proc. Zool. See. 1854, p. 13. 



