158 Nicholls Axi) Barxks. — Two Ncv T< n ctiirial Isopods. 
Habitat. — Tliis Kpeeies lias been taken on t)ie beaeli at Leighton 
and Cottesiue from tightly rolled balls of Cymodoce stalks washed 
u}; on to tlie sliore. Probably it enters these from the sand at or 
near tide mark. They may Ije submerged at times. Their colour 
liarmonizes wonderfully with the Avhite sand of the sea shore and 
this, witli their jiower of curling into a ball, makes them difficult 
to distingidvsh. 
Kemarks: This siiecies appears to be intermediate in structure'; 
betAveen ^1. cuchroa and A. oinJinoAs. In the general form of the 
body A. pallida resemljles A. cuchroa and, as in that species, the 
uropods have the outer ramus spatulate. In the condition of tho 
eyes however, it resembles A. opiJtensis. The degree of develop- 
ment of the eyes is probably correlated Avith the habits of the 
animal and not to be regarded as of generic value, as Chilton 
seems inclined to assume (1901, p. 132). 
The antennules have the usual three joints, the articulation 
of the third joint being \a*ry indistinct. In the antennae the 
fourth j(ont of the flagellum is similar to that of A. opiheiisus, 
being longer and more slender than in A. cuchroa. 
The first and second maxillae as in the other two species of 
Actaccia, resembles in g('iieral structure those of Scyphax as figured 
by Chilton (1901, PI. XIV, hg. 2). In the mandibles the lower 
tuft of setae Te})resenting the molar tubercle appears to be in 
tlie form of a single brushdike seta, Avhile the masticatory lobe 
of the maxillipedes has, in addition to a stout curved spine, a 
jointed lash differing from that figured for A. opihensu^. 
The dactylar setae on the legs are distinctive in shape. 
List of References. 
1892 — G. M. Thomson: Proc. Roy. Soc. Tasm. 1892 (p. 12). 
1901-Chilton: Trans. Linn. Soc. London Zool. Yo\. VIII, Part IV, 
pp. 121-132. 
19<15 — Richardson: Monograph on Isopods of North America, Bulb 
LbS. Nat. Mus., No. 54, p. 639. 
1912 — Richardson: Description of a Noav Terrestrial Isopod belong- 
ing to the genus Cubaris from Panama. Pr. Proc. U.S. 
Nat. Mus., Vol. 42, pp. 477-479. 
1919 — Collinge: Contributions to a knoAvledge of the Terrestrial 
Isopoda of Natal, Part II, fr. Ann. Nat. Mus., Vol IV, 
Part 1, pp. 229-233. 
1924 — Panning: Isopoda, Band II, Lieferung 3 der Land-und Buss- 
Avasserfauna Deutsch-BudAvestnfrikas ( Hamburg) . 
