90 



•ENDEAVOUR" SCIENTIFIC RESULTS. 



II.— REPORT ON THE MOLLUSCA. 



Part I. 



I. — Introduction. 



Through the kindness of the Hon. the Minister for Trade 

 and Customs, the writer, in August and September, 1909, 

 enjoyed an opportunity of accompanying the Director of 

 Fisheries on a cruise of the Fishery Investigation Ship, 

 "Endeavour." The voyage extended from Melbourne to the 

 Nuyts Archipelago, South Australia. At every opportunity 

 Mr. Dannevig gave me facilities for using my dredge. By 

 this means a large number of Invertebrates, not procurable 

 by the trawl, were obtained. The largest collection was made 

 on August 28th at a depth of 95-100 fathoms, south of Cape 

 Wiles, South Australia, the precise position being thirty- 

 nine and a half miles S. 43 E. from Liguanea Island, 

 itself about four miles from Cape Wiles. Here three 

 full loads of the bucket dredge were lifted and sieved. 

 The bottom temperature here was not noted, but at 80 

 fathoms, a short distance away, it was i4'o Cent. { = ^y'2 

 Fahr.), and the surface at midnight was i2'75 Cent. ( = 52*2 

 Fahr.). It was in this neighbourhood that in January, 

 1905, Dr. J. C. \'erco, from the s.s. "Lady Diana," made a 

 successful haul thirty-five miles south-west of the Neptune 

 Islands in 104 fathoms, and whence he has recorded so many 

 new species. 



Including fragments, illegible or undetermined forms, the 

 Cape Wiles haul contained more than three hundred and fifty 

 species, of which I record two hundred and twenty-six. This 

 agrees with my experience in New South Wales and Tas- 

 mania, 1 indicating that the molluscan fauna of a vard or two 

 of the margin of the Australian Continental Shelf consists of 

 from two hundred and fiftv to three hundred and fiftv species. 



This is richer than usual. Based chiefly on American 

 experiences. Dr. W. H. Dall^ estimates that about four 

 hundred species would constitute an entire fauna of shell- 

 bearing molluscs from an ordinary region between the limits 

 of 40-60 degrees Fahrenheit. 



1 Hedley— Rec. Austr. Mus.. vi., 1907, p. 273; Op. rit . vii.. 1908. p. 109. 



2 Dall I'i: Harris-Bull. U.S. Geol. Survey, No. 84, 1892, j.. 26. 



