Nicholls — Two New Phreatoicids. 
181 
the Northern Territory, the first instance of a Phreatoicid from the 
Tropics. Hitherto, the most northerly records for this family were 
the Barrington Tops in N.B.W., S. Lat. 32°, Perth, in W.A., in the 
same Latitude, while P. latipes from South Australia was found at 
Coward, 29° South Latitude. The fossil form, discovered at New- 
town, Sydney quite probably ranged as far north as these. 
At my request, 1 was most courteously allowed to remove certain 
of these Northern Territory forms for examination. They are 
described belo-vv, a new genus bejng required for their reception, the 
species being named in compliment to Mr. Kershaw. The species, 
taken at the Buffalo proved, likewise, to be new, this being named 
after my friend and enthusiastic fellow collector, Mr. A. E. Joyner, 
of Perth. 
A consideration of these two new forms and a rovieAv of the 
structure of such other species as I have been able to examine, has 
convinced me that the Australasian species referred, hitherto, to 
the genus PhreatoicuSj fall into two quite definite and readily separ- 
able groups, sufficiently distinct to warrant their assignment to 
separate genera. 
As was stated in an earlier paper (1924), it was only after very 
considerable hesitation that I had referred the M'estern Australian 
form P. Untoni to the genus Phreatoicus, a hesitation which Dr. 
Chilton had previously experienced when describing P. latipes. 
Accordingly, I now propose to establish for all the loA\land 
forms from Western and Southern Australia, a new genus 
Amphisopus, all these species having in common a number of features 
elsewhere found together only in the Amphipoda. To this new 
genus, however, the species from the Northern Territory eannot be 
assigned, nor does it fall within the accepted definition of Phreatoicus; 
consequently the recognition of a second new genus seems necessaij 
and for this I propose the name Eophreatoicus. The remaining 
forms, distributed in the subterranean and surface waters of New 
Zealand, the Highlands of Tasmania, and the Sub-Alpine regions of 
Eastern Australia should, so far as I can judge, be retained in the 
genus Phreatoicus Chilton, the new species P. joyneri, also, properly 
belonging here. The position of P. capensis Barnard is uncertain, 
and in the absence of material 1 can come to no conclusion, but, 
judging from Barnard’s figures (1914, PL 23, 24) and his descrip- 
tions, I incline to the opinion that it will be found to occupy a 
position intermediate between Eophreatoicus and Phreatoicus.^ In 
some respects, indeed, it appears actually more primitive than either 
of these; a consideration of this matter is deferred, however, to a 
later chapter, where the inter-relationships of the several forms are 
discussed. 
