THE TERRESTRIAL ISOPOD ELUMA CiELATUM. 103 
On the Terrestrial Isopod Eluma cadatum (Miers) = pitrpurascens, Budde- 
Lund. By Walter E. Collinge, D.Sc, F.L.S., Keaper of the 
Yorkshire Museum, York. 
(Plate 8.) 
[Read 15th June, 1922.] 
The genus Eluma was described by Budde-Lund * in 1885 for a species of 
Terrestrial Isopod which he named E. purpuraseens. The description of 
both the genus and species is imperfect, and no figures accompany it. 
As a doubtful synonym Budde-Lund gives the Armadill'ulium ca'latum of 
Miers, which was described and figured by Miers in 1877 from specimens 
obtained at Cayenne, French Guiana, South America t- 
A careful comparison of tlie description and figures, both imperfect, 
with specimens received from Mr. D. R. Pack-Beresford, from the Hill of 
Howth, Co. Dublin, Ireland, leaves no doubt, in my mind, as to the identity 
of Miers's species with these. His specific name ccelatum therefore has 
priority, and must replace that o( pui-purascens. 
Neither Miers or Budde-Lund gave any figures of the structure, and their 
i-eferences are ver}^ brief and in some points scarcely accurate ; I am there- 
fore venturing to redescribe and figure the genus and species. 
Mr. Pack-Beresford % figures the external appearance of this species, but 
his illustrations are not correct in all details. Verhoeff § has given two 
figures of parts of the exoskeleton. 
The Rhacodes inscriptus of Koch ||, regarded by Dollfus and Budde-Lund 
as a synonym of T^los latreillei, Aud. & Sav., was thought by Eaton If to be 
referable to this species. 
Eluma, Budde-Lund. 
Body oblong-ovate, strongly convex, setose^ and closely and minutely 
punctured. X'ephalon strongly marginate, with median aud lateral lobes ; 
epistome with sloping dorsal portion and keeled. Eyes simple, very small. 
Antennulse small, 3-jointed, terminal joint conical. Antennae somewhat 
short, flagellum bi-articulate. Pleural plates of mesosomatic segments 2-7 
slightly excavate anteriorly, ventral margin indeutate on segments 2-4, trun- 
cate on 6-7. Coxopodite of first segment separated from the pleuron and 
* Crust. Isop. Terr. 1885, p. 48. 
t Proc. Zool. Soc. Loud. 1877, p. 665, pi. 67. figs. 3-3 b. 
% Irish. Nat. 1908, p. 255, pi. 10. 
§ Arch. f. Biontologie, 1908, Bd. ii. p. 371. 
II In Kosenhauer's ' Die Thiere Andalusiens,' 1856, p. 422. 
U Ann. & Mag. Nat. Hist. 1882 (s. 6), vol. x. p. 360. 
