PTYCHORHYNCHUS II49 



Although the original description of this species is very 

 full I am unable to feel any certainty as to where it belongs. 

 Nothing is known of the anatomy and the entire umbonal re- 

 gion is so badly eroded in the specimen figured that no idea 

 can be formed of the beak sculpture. The form is almost 

 exactly that of Unio complanatus save that it is more widely 

 and distinctly biangulate behind. I place it with some doubt 

 near the Unio apicellatus of Pleude. The solid pseudocardi- 

 nals, the posterior plications and its form and color are some- 

 thing like that shell. 



Haas has recently, (Nachr. Deutsch. Mai. Ges., 1913, p. 33), 

 made this species the type of a new genus, Schepmania. 



Van parcesctilptum (von Martens). 



"Shell oblong, compressed, thick, closely, concentrically stri- 

 ate and sculptured on the posterior slope near the umbones 

 with upward curved folds, often slightly divided ; very short 

 and rounded in front, elongate and subtruncate behind ; um- 

 bones quite compressed, eroded ; posterior dorsal margin sub- 

 horizontal as far as the sinulus, thence with a very obtuse an- 

 gle sloping gradually to one-half of the height of the shell ; 

 posterior margin straight, slightly oblique, separated from the 

 ventral margin by a more or less distinct angle ; ventral margin 

 posteriorly and in the centre subhorizontal, very slightl)^ 

 curved, in the anterior third at first a little, then sharply as- 

 cending. Nacre milky-white, slightly pearly ; cardinal tooth 

 of the right valve strong, conic-triangular, crenulate ; poste- 

 rior cardinal tooth of the left valve not quite so strong, conic, 

 anterior weak, compressed triangular ; laterals straight. 

 Length 70, height 43, diam. 20 mm." (von Martens). 

 Type locality, Guleh River, East Borneo. 

 Unio (Ouadrula) nieiiwenhousi var. parcescuiptus von Mas- 

 tens, S. B. Ges. Naturf. Fr., 1903, p. 425. 

 Schepmania parcesculpta Haas, Con. Cab., Unio. 1910, pi. xii, 



fig- 4- 



"Differs from the species described 'by Schepman as well as 

 from the typical form from East Borneo by the weaker sculp- 



