67 
The essential characters, as apart from Trochus , will be the 
columellar depression, the step-like form of the whorls, a simple 
columella, and an aperture without plicae or teeth. 
Trochus ( Scalcetrochus ) lindstromi is unquestionably allied 
to the shell called by de Koninck Euomphalus biysbyi , but the 
apical angle of the two shells is very different. The step-like 
form of the whorls is met with in some species of l)e Koninck’s 
genus Flemingia , but this genus is also umbilicate. 
RE-DESCRIPTION OF PSEUD APIIRITIS BASSI, CASTELN. 
By .1. Douglas Ogilby. 
TriK Museum having had the good fortune to receive lately, 
through the Department of Fisheries, a line example of this 
little-known species within a day or two of its capture, I think 
that a full description thereof will not be out of place. 
It is due to the discernment of Mr. Frederick Smith ers, 
Travelling Inspector of Fisheries, that 1 am enabled to add 
this interesting fish to the already rich ichthyological fauna of 
the colony. 
The example described below was obtained by that gentleman 
at Bega in fresh water, and he is of opinion that it is not 
uncommon there, and descends also into brackish water • the 
present specimen is six and a quarter inches in length, but 
Mr. Smithers tells me that it grows to a larger size. 
In 1872 Count Castelnau published a description of this fish 
from a single specimen taken in Bass’ Straits, and formed for 
its reception a new genus, Pseudaphritis , on grounds however 
which prove to be entirely inadequate ; these grounds he 
himself defines as follows: “ the scales are rather large ; the 
first dorsal has seven rays, (i.e, eight spines), and just in front 
of the anal there is a short fin composed of two spines.” These 
three reasons for constituting a new genus may be disposed of 
as follows : in our specimens of Pseudaphritis bassi the number 
of scales on the lateral line varies between sixty-one and 
sixty- three j in Aphritis urvillii between sixty-three and 
sixty-live $ and in all our examples of the latter the first 
dorsal fin possesses seven spines, and the anal is preceded by 
two small semi-detached spines. It follows therefore, as a 
matter of course, that Castlenau’s name becomes a mere 
synonym of Aphritis , 
