192 1.] B. Prashad : S'liinatr an Molluscs. 467 



Pythia plicata (Fer.). 



1S07. Pyfliia plicnta, v . Martens, op. cif., pp. 131-133. 



The only specimen of this species was collected in the man- 

 grove-swamps at Belawan (Deli). I have no doubt as to its correct 

 identification. 



Pythia undata (Less.). 



1897. Pythia undata, v. Martens, op. cit., pp. 139-140. 



A single specimen of this species, collected in the mangrove- 

 swamps at Beiavvan (Deli), is represented in the Sumatran collec- 

 tion. 



Genus Cassidula, Fer. 



Cassidula auris-felis (Brug.). 



1897. Cassidula auris-felis. v. Martens, op. ci't., pp. 141. 142. pi. viii, 

 figs. 12-14. 



A larije number of specimens of this variable species were 

 collected in the mangrove-swamps at Belawan (Deli), from the 

 mouth of the Soengei Batang Kwis (Serdang) and at Perbaoengan 

 (Serdang). Most of these resemble fig. 13 of von Martens, but a 

 few are like fig. 14 as regards the shape of the mouth. 



Genus Auricula, lyam. 



This genus is represented by four species, two of which are 

 new. The descriptions of these new forms were drawn up by Dr. 

 Annandale and are here included to make the account of Mr. den 

 Doop's collection complete. 



Auricula midae (Linn.). 



1897. .Auricula Midae. >'. Martens, op. cit.. pp. 150-152. 



I have adopted with von Martens the name A. midae in pref- 

 erence to the name A. auns-Midae used in Kiister's Monograph 

 in Martini and Chemnitz Conch. Cab. 



A fairly full account of the anatomy of the species is included 

 in Quo}' and Gaimard's work ' and the radular teeth are also figured. 



In the Sumatran collection it is represented by a few specimens 

 collected in the mangrove-swamps at Perbaoengan (Serdang) and 

 at Belawan (Deli). A few were also collected on the sea-shore at 

 Perbaoengan (Serdang). 



Auricula judae (Linn.). 



1807. Auricula Judae, v. Martens, op. cit.. pp. 154-158, pi. vii, figs. 

 •6—11. 



Von Martens has treated the question of the various forms of 

 this variable species in great detail, and published good figures. 



In the Sumatran collection there are three specimens collect- 

 ed by Mr. den Doop along with those of A. midae in the mangrove- 



' Voy. .'\stfolabe Znol. II. p. 156, pi. xiv, figs, i — 14 (1832}. 



