A CAVE ISOPOD 377 
(Linn.) is a species distributed almost all over Europe in 
great abundance. The details of its organisation, external 
and internal, are explained, with a clearness of language 
and drawing which leaves nothing to be desired, in the 
‘Histoire naturelle des Crustacés d’eau douce de Norvége’ 
by G. O. Sars, 1867. M. Dollfus says that aquaticus is 
completely displaced in Palestine by his new species, 
Asellus coxalis. Harger mentions Asellus communis, Say, 
as common in the fresh-water ponds and streams of New 
England. For other species, and the bibliography of the 
genus, the ‘ Notes on the Family Asellide,’ by Dr. Boval- 
hus, should be consulted. 
Maneusellus, Harger, 1876, was named to take the 
place of Asellopsis, Harger, 1874, preoccupied. This genus 
is exceptional in regard to the mandibles which have no 
‘palp,’ being otherwise very like Asellus. Mancasellus 
tenaz (S. I. Smith) and Manecasellus brachyurus, Harger, 
are found in the fresh waters of North America. 
Cecidotea, Packard, 1871, is without eyes, has the 
seventh joint of the limbs not bifid, and the uropods elon- 
gate, with two unequal branches. The species Cecidotea 
stygia is found in the Mammoth and Wyandotte Caves and 
in wells in Indiana. The absence of eyes does not distin- 
guish it from Asellus, for some of the species of that genus 
are also blind. 
Janira, Leach, 1814, is a marine genus, dorsally not un- 
like Asellus, but the second antennz have a small scale or 
exopod ; the first limbs of the pereeon have the sixth joint 
scarcely expanded; the first pleopods in the female form 
a subcircular operculum. The uropods are two-branched. 
The only British species is Janira maculosa, Leach. In 
regard to the American species, Janira alta (Stimpson), 
Harger says of the pleopods in the male :—‘ The thickened 
opercular plates are three in number, viz., a pair of semi- 
oval plates at the sides, and a more slender median plate 
presenting traces of a suture along the middle.’ This 
formation is probably characteristic of the genus, and no 
doubt, as explained by Hansen for Eurycope, the fused 
plates represent the first pleopods, and the semi-oval plates 
