BY C. HEDLEY. 545 



nodules on the ribs. The rim of the prodissoconch stands 

 out from the summit of the valve; it is semicircular, the edge 

 turned up, the interior tumid, and the centre umbilicate. Length 

 2-45, height 3*25, depth of single valve I '3 mm. 



Hah. — In shell sand on Manly Beach, numerous specimens. 

 (Miss L. Parkes). 



T y p e. — To be presented to the Australian Museum. 



By its sculpture the present form is well distinguished from 

 other Australian species. But it closely resembles P. costata 

 Bernard, from South New Zealand, which slightly differs by fewer 

 and bolder radial ribs. 



While on the subject of Philohrya I may take this opportunity 

 of observing that the genus Limarca of Tate* is synonymous. 

 Prof. Howchin has very kindly permitted me to examine the 

 types preserved in the School of Mines, Adelaide. Mr. J. 

 Dennant also lent me co-types received from the author. From 

 both sets it is apparent that in creating the genus Prof. Tate 

 used two species of different genera, one a Philohrya, the other a 

 Limopsis. But the example labelled " type " is the Philohrya, 

 and to it rather than to the Limopsis is applicable the epithet 

 " angustifrons," and the opening descriptive phrase, " very 

 inequilateral." The Limopsis is an aberrant form, and probably 

 undescribed. Before returning his example to Mr. Dennant, 

 I took the accompanying sketch (Plate xxxii., fig. 17) of the 

 Limopsis hinge. 



Arca venusta Dunker. 



Dunker, Zeitschr. f. Mai. 1852, p. 59; id. Novitat. Conch. 1867, 

 p. 91, pi. xxxi., f.l. 



This bivalve is an addition to the Australian fauna. As 

 separate valves it occurs frequently on the beach at Mapoon, 

 entrance to the Batavia River; and I noticed it again at Karumba, 

 mouth of the Norman River, Gulf of Carpentaria, Queensland. 

 Dr. E. Lamy, of Paris, a specialist on this genus, has kindly 

 confirmed my identification. 



* Trans. Roy. Soc. S. Austr. viii. p. 135, pi. viii., f.5, a, h. 



