PnOLAS OBTTJRAMENTUM. — HEDLEY. 
55 
PHOLAS OBTTJRAMENTUM ; an UNDESCRIBED 
BIVALVE from SYDNEY HARBOUR. 
By C. Hedley, F.L.S. 
[Plate XIV.] 
In the course of a critical examination of various Mollusca 
from Port Jackson, specimens of the only Pholas reported thence 
passed under review. This species has hitherto been accepted as 
P. similis by all writers and collectors who have occupied them- 
selves with the marine mollusca of our coast. This identification 
appears to have originated with G. F. Angas, who in his “ List of 
additional Species of Marine Mollusca to be included in the 
Fauna of Port Jackson and the adjacent Coasts of New South 
Wales/’* enumerates as species 93 : — 
“Barnea similis. Pholas similis , Gray, MS. Brit. Mus. ; Thesaurus 
Conch, pi. ciii., f. 12 — 14; ‘Bottle and Glass’ rocks, in 
sandstone (Brazier).” 
This entry is repeated verbatim by Mr. T. White! egge in the 
“ List of the Marine and Freshwater Invertebrate Fauna of Port 
Jackson and the Neighbourhood.”! Mr. Brazier informs me 
that this determination was also supported by the late G. B. 
Sowerby. 
Prof. Tate records Barnea similis , Gray,J as “burrowing in clay 
at low tide mark, Port Lincoln, St. Vincent Gulf, and south-east 
coast [of South Australia] ; also in Tasmania.” 
On examining the statement of Angas closely, our faith in his 
accuracy is weakened by observing that Gray’s name was not, 
as he states, a manuscript one. It was first published with a 
description in 1835 in the Appendix of Yates’ New Zealand, 
p. 309, and it again appeared, with further information, eight 
years later, in Vol. ii. of Dieffenbach’s New Zealand, p. 254 
where the author remarks that it is “ very like Pholas •parvus , but 
larger, broader, and more acute in front.” 
Between the New Zealand and the Australian species a dis- 
crepancy at once appears on comparing examples of the Port 
* Proc. Zool. Soc., 1871, p. 99. 
f Journ and Proc. Boy. Soc. N.S.W., xxiii. (1889), p. 234. 
t Trans. Eoy. Soc. S. Australia, ix., p. 80. 
Sept. 1S93] 
