ISOrODA. 
Crust. 36 
united above, but separated at the sides by short incisions. Operculum 
with a single apical plate. Palpus of maxillipeds three- jointed. Type, 
Idotea nodulosa (Kroyer). Harger, 1. c. p. 374. 
Arcturus hajffini, var. n. feildeni\ Miers, in Nares’s Narrative, &c., ii. 
p. 243, pi. ii. fig. 1, Floeberg Beach, 82° 27' N. lat. 
Arcturus linearis^ new name for gracilis (Stebbing, Tr. Devon Ass. 
1874) ; Stebbing, Ann. N. H. (6) i. p. 36. 
Arcturus hystrix, sp. n., Sars, Arch. Math. Naturv. 1876, p. 350, Nor- 
thern Sea, 62° N. lat., 1° E. long., 412 fath. 
Leachia granulata, sp. n., id. 1. c. p. 351, Northern Sea, same locality. 
Astacilla (= Leachia, Johnst.) americana, sp. n,, Harger, 1. c. p. 374, 
St, George’s Bank, New England, on Primnoa. 
Munnopsid^. 
Eurycope gigantea, sp. n., Sars, 1. c. p. 353, size 33 mill,. Northern Sea, 
63° N. lat., 3° E. long., 525 fath. 
Eurycope rohusta, sp. n., Harger, 1. c., p. 375, Gulf of St. Lawrence, 
220 fath. 
Asellidj). 
Asellus aquaticus (L.). Leydig gives anatomical and histological 
notes on the antennae, eyes, skin, and respiratory organs ; Z. wiss. Zool. 
XXX. suppl. pp. 251-265, pis. x.-xii. (partly). Rabl. Ruckhard opposes 
the view that the fine featherlike bristles on the antennae are sensitive ; 
SB. nat. Fr. 1878, pp. 148 & 149. 
AsellUs cavaticus (Schiodte) : differences from aquaticus (L.); Leydig 
Z. wiss. Zool. xxx. suppl. p. 268. 
Nannoniscus hicuspis, sp. n., G. 0. Sars, Arch. Math. Naturv. 1876, 
p. 352, Northern Sea, 63-65° N. lat., 3° E.-7° W. long., 500-1100 fath. 
Oniscidje. 
F. Leydig describes the structure of the antennae and eyes, the sculp- 
ture of the skin the respiratory organs and their opercular plates, in the 
terrestrial Isopoda of Germany ; Z. wiss. Zool. xxx. suppl. pp. 251-265, 
pi. X. figs. 14-25, & pis. xi. & xii. He also gives several interesting notes 
on the differences and habits of the known species occurring in Southern 
Germany, chiefly (Brandt), 3 species of Itea, Oniscus 
murarius (Cuv.), Porcellia armadilloides (Lereb.), scaber and pictus 
(Brandt) ; 1. c. pp. 265-271. 
Ligia quadrata (Hutton, MS.), sp. n., Thomson, Tr N. Z. Inst. xi. 
p. 232, pi. X. fig. A 4, Dunedin, New Zealand. 
Oniscus punctatus, sp. n., id. 1 . c. p. 232, pi. x. fig. a 3, Dunedin, New 
Zealand. 
Actoniscus, g. n. Eyes small; antennae geniculate at the third and 
fifth segments ; flagellum four- jointed ; terminal segment of maxillipeds 
lamelliform ; legs all alike ; pleon of six distinct segments ; basal seg- 
ments of Uropoda dilated and simulating the coxae of the preceding seg- 
