126 ON SOME NAKKD AUSTRALIAN MARINE MOLLUSCA, 



ON SOME NAKED AUSTRALIAN MARINE MOLLUSCA. 

 Part I, 



(Plate VII.). 



By C. Hedley, F.L.S. 



(Communicated h»j permission of the Trustees of the Australian 

 Museum). 



Partly because they offered no trophies to grace the collector's 

 cabinet and partly because the literature treating of the subject is 

 both meagre and difficult of access, the Australian naked mollusca 

 have been little studied. 



A recent donation to the Museum by J. P. Hill, Esq., F.L.S., 

 Demonstrator of Biology of the Sydney University, comprising 

 several species of shell-less mollusca, and which in the course of 

 official duties required determination, brought forcibly to my 

 notice the poverty of published information regarding them. 



Commencing my inquiries with a huge Pleurohranchus (as 

 understood by Fischer), I found that in Australia two species 

 only are as yet recorded, P. punctatus* Q. and C, Voy. Astrolabe 

 Zool. ii. p. 299, pi. xxii. ff. 15, 19, from Jervis Bay, N.S.W., and 

 P. angasi, described and figured by E. A. Smith, "Report on the 

 Zoological Collections made in the Indo- Pacific Ocean during the 

 Voyage of the Alert, 1881-2," p. 88, pi. vi. ffi K, K'; and collected 

 in Sydney Harbour by Dr. Coppinger. 



A Pleurobranchidium maculatum was collected, figured and 

 described by Quoy and Gaimard in association with P. functatus. 



If we extend our survey to New Zealand we find another species 

 P. ornatiis, Cheeseman (P.Z.S. 1878, p. 275, pi. xv. flf. 1, 2). 



* I am indebted to the kindness of Pi'of. Tate for a reference to this 

 species. 



