142 
racters which, while never overlapping, show considerable elasticity, 
and tend to approach more or less the characters of the other 
groups. I have, therefore, thought it best to assign to these groups 
subgeneric value only, considering as genera those specific aggrega- 
tions which show n0 approach whatever to any other similar spe- 
cific group. 
Key to the subgenera of Comanthus. 
a? III Br 2, rarely 4 (3 + 4) Comantheria. 
a? III Br 2 externally, 4 (3 — 4) internally SLSKADIAGE 
a? IUIBr 4 (3 + 4), rarely 2 Comanthus s. 8. 
The subgenus Comanthus as here restricted contains two in- 
completely differentiated specific groups, which, although intergrading 
in all their characters, nevertheless are usually distinct enough, and 
occupy Characteristic geographical areas. One of these, which may 
be conveniently known as Bennettia (typified by Alecto bennetti 
Miilller 1841), occurs from the southern coast of Australia north- 
ward to Japan and eastward to Samoa, and is distinguished by 
having the cirri always present and numerous, compressed distally, 
and usually stout, and the II Br series invariably 4 (3 + 4); the 
other, which may be called Validia (typified by Comatula rotalaria 
Lamarck 1816) occurs throughout the East Indian region; the cirri 
are few, small, and weak, or quite absent, and one or more of the 
II Br series are 2 instead of 4 (3 + 4). 
The type of the subgenus Comanthina may be taken as Åc- 
tinometra nobilis P. H. Carpenter, and that of Comantheria as ÅAn- 
tedon briareus Bell; the type of Comanthus is Comanthus intricata 
A. H. Clark = Actinometra valida P. H. Carpenter. 
By an unfortunate chance the generic name Comanthus Was 
first actually published in the paper containing the preliminary de- 
scriptions of the new species in this collection, it having been first 
written in a paper on Philippine crinoids, which, however, did not 
appear until thirteen days later. In this paper two species were 
described under this generic name, Comanthus intricata and C. de- 
cameros. The latter has been separated out as the type of the 
