284 RECORDS OF THK AUSTRALIAN MUSEUM. 



deep water. I am struck l)y the repetition in the " Miner's " haul 

 of most species taken oft' Wollongong, fifty miles south ; and off" 

 Cape Byron, three hundi'ed and sixty miles north. But if the 

 series before me represents a tentii or even a quarter of all the 

 mollusca of the continental shelf, then we are grasping a fauna as 

 rich or richer than any known. 



Of this collection many ajiparently new are too imperfect for 

 description. Otheis are suitable for publication but time has not 

 allowed the preparation of drawings and descriptions. As species 

 observed in previous dredgings are here first introduced, so I shall 

 hope for a future opportunity to publisli those now put; aside. 



Five years ago a collection made anywhere from our continental 

 shelf would have presented quite thirty per cent, of new species. 

 This might fairly be ranked as a new fauna. As collections are 

 described, the proi^ortion of novelties in any particular haul will 

 decrease. When reduced to three or four per cent, we might 

 claim to have a fair knowledge of that fauna. A high proportion, 

 about sixteen per cent., appears in the present collection, conse- 

 quently much work is to be performed before we gain a tolerable 

 acquaintance with the mollusca from 20-100 fathoms off" Sydney. 



In the first of these reports^ I drew attention to the appearance 

 in a recent state, of several species previously known as Tertiary 

 fossils. I now add to these Trivia avellanoides, McCoy. Dr. 

 J. C. Verco, who is publishing details, informs me that the differ- 

 ence between my Astele hilix (now i-emoved to Basilissa) and 

 Tate's Seguenzia radlalis are hardly more than varietal. When 

 a oood knowledge of both recent and fossil Australian shells is- 

 combined in one brain, the list of survivors will probably be en- 

 larged. The types of the new species are to be preserved in the- 

 Australian Museum. 



Dr. J. C. Verco is now describing shells from the continental 

 shelf of South Australia and finds there a number of the species 

 here recorded. I have benefited by comparison and interchange 

 of specimens and it is hoped that duplication of work has been 

 avoided. 



My thanks are due to Mr. G. M. Goldfinch, a volunteer assis- 

 tant, who undertook the sorting and separation of the collection. 

 Without his help I should have been unable to present this re- 

 port at so early a date. 



Hedley— Mem. Austr. Mus., iv., 5, 1902, \\ 287. 



