•88 
Nicholls axd Hakxes — A New Terrestrial Isopod. 
latioasliip ^vitll that form. Advantago Avas taken of the oi)portunity : 
afforded l>y a rca-ent viisit to Adelaide to examine specimens in the 
collection of the S.A. Mnseunp and it then became apparent that ■! 
our Western Australian form also showed marked affinities Avith j 
Thiloseia salina Baker, knoAvn only from salt Avater pools near the i 
South Australian Coast. Chilton states {19:^0, ]). 725) tliat he had ; 
cx])erienced considerable difficulty in assigning the new species to its • 
jiroper ])lace iji the Oniscoi<lea, and he finally decided to constitute j. 
for it a new genus. He ])ointed out that its nearest affinities AAuth ; 
existing genera Avere Avitli Pliiloscia, from AA'hicli, hoAvever, it differs ; 
in a number of characters. Baker, in referring the South Austra- j 
ban s])ecies 1o Pliiloseia, a])])ears to haA'O lieen imaAvare of Chilton ^s i 
pa])er. 
It has seemed best to us to accept Chilton’s vioA\' of the : 
generic distinctness of this s])ecies, and since all three forms are 
much alike in mode of life (in or upon the shores of salt AA’ater), 
and agree closely in their structural ])cculiarities, aa’c suggest that 
Baker’s s])t‘cies should lu‘ transferred to Haloniscus. 
For the West Australian form the name Haloniscus steplieni is 
proposed, the specific designation being in compliment to Mr. Wm. 
Stephejis, of Perth, througli AA'hose kindness this collecting trip Avas 
rendered possible. 
Gen. Haloxxscus. Chilton. ; 
1920, Haloniscus (8p. typ. H. searlei). (dias Chilton, Proc. Linn, 
Soc. N.S.W., V ol. 4:1, Part 4, p. 723. 
Body elongated iiarroAc o\'al, convex; dorsal surface smooth, 
covered Avith fine hairs. Cephalon rounded in front, Avitliout lateral 
lobes. iMesosome Avith the side plates not greatly expanded. Meta- 
S( me very slightly narroAved; third, fourth and fifth segments AA'ith 
distinct e])imera; last segment largo and Avitli AA'cll-deATloped lateral 
portions; extremity sub-triangular. Eyes present, lateral in position. 
First antenna minute three-jointed. Second antenna comparatively i 
short, flagellum three-jointed. Legs Avell dcA'eloped and increasing ' 
ill length posteriorly, the anterior four pairs prehensile, more or less 
sub-chelate; the fifth, sixth and seventh, simple; dactyls bi-imguieu- 
late, Avithout special daetylar seta. Pleoiioda conspicuous AA'ith aa'cII . 
developed opercular plates lacking air cavities. Uropoda exposed, 
moderately developed, Avith peduncles reaching beyond the end of 
metasome; inner ramus attached only slightly in front of the 
outer. ; 
hemarl's: Closely related to Philoseia, but differing from that ^ 
genus in the scarcely narroAved metasome, the possession of a large 
terminal segment, with well-developed lateral expansions. Of per- 
haps lesser importance as distinctiA'e features are the comparatively 
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