O77 DET AGU, 
[from “Transactions of the Royal Society of South Australia,” 
vol. xaxxiti., 1909.) 
NOTES ON SOUTH AUSTRALIAN MARINE MOLLUSCA,. 
WITH DESCRIPTIONS OF NEW SPECIES.—-PART XI. 
By Jos. C. Verco, M.D. (Lond.), F.R.C.S. (Eng.). 
[Read October 5, 1909.] 
PLrarrs XNXIL, XXII, and Parr XXVI. 
My paper deals with the genus 7Z’riphora. I haye 
adopted this name, in accordance with the conclusion ar- 
rived at by Mr. Hedley as to Blainville’s priority of publi- 
cation. 
Hitherto only four species have been recorded for South 
Australia, which furnished the type specimens of them all— 
viz., T. angasi, 7. festiva, T. pfeifferi, all of Crosse and 
Fischer, and 7. settula, A. Adams. Several others were 
known to occur here, but their identification was difficult. 
Mr. Hedley, in a valuable contribution to the Proc. Linn. 
Soc. of New South Wales, 1903 (1902), on the Triphoridz: 
of that State, cleared away much of the obscurity which had 
enveloped some already described species from Port Jackson,. 
and added several new ones to the list. Specimens of nearly 
all these, kindly supplied by him, have aided considerably 
in unravelling the tangle of our South Australian forms. Six 
of his eight novelties are represented here, and four of the 
six species described by other authors. The task has been 
difficult, even with this clearance. A very large number of 
shells, collected during several years’ dredging, furnished 
not only many species, but a most perplexing number and 
series of variants in nearly every species; and what with 
macromorphs and micromorphs, juveniles and adults, nar- 
row and obese forms, differences in relative size of pearl rows, 
validity and invalidity of the sutural thread, rolled, 
bleached, or fresh shells, typical and atypical colouration,. 
accurate specific determination at times seemed unattainable. 
Even now it is impossible absolutely to decide whether some 
of my enumerated varieties are not distinct species, and some 
of my newly-named species may not prove eventually to be 
only variants. Of the four species enumerated in Adcock’s 
“Handlist of Aquatic Mollusca of South Australia,” 1893, 
one has been omitted, wiz., 7. scitulus, A. Adams. It was 
described from a Port Lincoln shell, but has not been re- 
cognized. A shell which in some respects conforms to the 
description has been dredged, but I refrain at present from 
30 naming it. To the remaining three species we have been 
