67 



The essential characters, as apart from Trochus, will be the 

 coluTuellar depression, the &tep-like form of the whorls, a simple 

 columella, and an aperture withont plicae or teeth. 



Troehufi (Scalcetrochus) lindstromi is unquestionably allied 

 to the shell called by de Koninck Eiwinphahis hir/shyi, 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 De Koninck's 

 genus Flemingia, but this genus is also nmbilicate. 



RE-DESCRIPTIOX OF PSEUDAPHRITIS BASSI, CASTKLX. 

 By .T. Douglas Ogilby. 



The Museum having had the good fortune to receive lately, 

 through the Department of Fisheries, a iine example of this 

 little-kno"n^n 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 Sraithers, 

 Travelling Inspector of Fisheries, that I am enabled to add 

 this interesting fish to the already rich icjithyological 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, Pseudajjlwitis, on grounds however 

 which prove to be entirely inadeqiiate ; 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 bet"ween sixty-one and 

 sixty- three ; in Aphritis tirvillii between sixty-three and 

 sixty-five ; 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 Ajjhritis, 



