930 MK. G. F. ANGAS ON AUSTRALIAN MOLLUSCA. [NoV. 28, 



Fam. VuLSELLiD^. 



111. Vulsella TASMANicA. 



Vulsella tasmanica. Reeve, Couch. Icon. Vulsella, pi. 1. f. 3. 



A rusty-brown species of irregular growth, covered with minute 

 flattened scales arranged in concentric ridges. In sponges &c., 

 Port Jackson. Length 1 inch. 



Fam. MoDioLARCiD^. 



112. MODIOLARCA SUBTORTA. 



Modiolarca suhtorta, Dunker, P. Z. S. 18.5G, p. 365. 

 Modiola subtorta, Reeve, Conch. Icon. pi. 10. f. 70. 



A small, brown, trapezoid shell, with the valves unequal and 

 slightly twisted. Cook's River, Botany Bay. Length 4 lines. 



Fam. AvicuLiD^. 



113. AVICULA PULCHELLA. 



Avicula pulchella, Reeve, Conch. Icon. Avicula, pi. 8. f. 22. 



A semitransparent, horny species, painted with more or less inter- 

 rupted reddish flames radiating from the umbones. Attached to 

 sea-weed, in deep water, Botany Bay and Middle Harbour. Length 

 1 inch. 



114. MaRGARITIFERA FIMBRIATA. 



Avicula Jimbriata, Reeve, Conch. Icon. Avicula, pi. 9. f. 25. 



A very variable species, both in colour and sculpture. Sometimes 

 it is nearly smooth, at others broadly furbelowed towards the margin 

 with long spout-shaped laminar scales. It is flattened, very broad 

 at the upper part, and squarely ovate. The colour varies from dark 

 horn or purple to whitish, more or less rayed with irregular purple 

 bands and blotches. The interior is brilliantly nacreous. The Avi- 

 cula placunoides. Reeve (Conch. Icon. pi. 17. f. GS), is probably only 

 a variety of this species. Found under pieces of rock at low water, 

 at Middle Harbour and Watson's Bay. Length 3 inches. 



115. Malleus ALBUS. 

 Ostrea malleus-albus, Chem. 



The ordinary " Hammer-oyster " of Australia, which ranges from 

 Port Lincoln to Moreton Bay. It occurs on the sandy flats in Broken 

 Bay ; and I obtained a young specimen in Middle Harbour, Port 

 Jackson. 



116. Pinna ZEYLANiCA. 



Pinna zeylanica, Gray, Appendix to Dieff'enbach's Travels. 

 This common Australian species is found at Brisbane Water. 



