314 Mr. H. J. Carter’s Contributions to our 
quently Dr. Gray divided Dr. Bowerbank’s genus into the 
genera ‘‘Seriatula” and “Eetyon,” allotting to the former our 
British species Chalina seriata, and to the latter Dr. Bower- 
bank’s ‘ West-Indian sponges,” viz. Hetyon sparsus &c. 
(Proc. Zool. Soc. Lond. 1867, p. 515). Schmidt, in 1864 
(Spong. adriat. Meeres, Ist Suppl. p. 35, Taf. iv. fig. 2), 
described and illustrated the European representative of Hetyon 
under the name of Clathria oroides, and in 1870 changed the 
name to ‘‘Chalinopsis oroides”’ for his West-Indian speci- 
mens (Spongienf. atlantisch. Gebietes, p. 60, Taf. v. fig. 2). 
There is yet another species that has come under my obser- 
vation, of which only a fragment about 24 inches long exists 
in the Bowerbank general collection at the British Museum, 
but sufficient for me to compile the following description 
under the name of 
Ectyon cylindricus, n. sp. (Pl. XIII. fig. 4, a-e.) 
Cylindrical, solid, curved (Pl. XIII. fig. 4, a, 5). Con- 
sistence firm, resilient. Colour brown ochre-yellow. Surface 
even, reticulate. Vents scattered, numerous, large, round, 
averaging 1-8th inch in diameter (fig. 4, d). Cribriform 
groups of “small holes” not present here. Pores not seen. 
Internal structure firm, compact, tough, elastic, traversed 
freely by the branches of the excretory canal-systems, which 
open at the vents mentioned (fig. 4, 6). Spicule acuate, 
curved, sharp-pointed, verticillately spined; average largest 
size 30 by 2$-6000ths inch in its greatest dimensions (fig. 4, c) ; 
verticils twenty-two in number, about 2-6000ths inch apart 
in the centre, diminishing in this respect towards the extre- 
mities, especially towards the point; spines about eight in the 
central verticils, becoming less in number towards the point, 
which is smooth for a short distance up; spicules forming the 
axis of the fibre and congregated into groups echinatingly on 
the outside, so that all the free surfaces of the cancellated 
cavities of the tissue and those of the excretory canals are 
thus rendered hispid. Size of fragment, which is cylindrical 
and represents a short segment only, of a large curve, about 
24 inches long by 1 inch in diameter, slightly compressed, 
as may be seen by the section (fig. 4, 4). 
Hab. Marine. 
Loc. West Indies. 
Obs. This not only differs in general form from all the 
foregoing species, but also in structure, which is compact 
throughout, and not clathrous, while the only holes on the 
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