more slender, but otherwise similar. P^ is similar to I',, but slightly smaller and shorter. P, is 
V5 nim. lono- wilh i 7 segments of which the distal bear traces of a comb. P. is very small 
and slender, 3 mm. long, with no trace of a comb. 
In the "Challenger" report Dr. P. 11. C.vrpentkr records (p. 304) under the name of 
Actinomctra pulcliclla a somewhat anomalous specimen which was dredged near the Kei Islands 
(5° 49' 1 5" S., 1 32° 14' 15" E.) in 140 fathoms. Aciinometra piilchella (now known as Xeo- 
comafella alafa) is confined to the Caribbean region, and belongs to a genus, Neocotnaiella, 
which is exclusively Atlantic, its representative in the Indo-Pacific region being the allied 
ComatcUa. 
This .specimen gave Carpenter considerable trouble ; at first he had believed that it 
represented a new species, and on p. 93 of the "Challenger" report he mentions it under the 
name of Actinometra difici/is, saying of it that "the two outer radials [i. e., the two elements 
of the IBr series], the two di.stichals [i. e., the two elements of the IlBr series] and the first 
two brachials are respectively united by syzygy." He refers to fig. 2 on pi. 52 as representing 
this specimen. 
The figure shows a much broken individual with about 18 arms; the dorsal pole of 
the centrodorsal is circular, broad and flat, 4.0 mm. in diameter; there were apparently about 
XX cirri which are 13 mm. long with 16 segments of which the longest are over twice as 
long as broad, and the last eight are broader than long; the brachials beyond the basal 
appear to be triangular, about as long as broad, judging from the regenerating arm in the 
upper right hand side of the figure.. 
It is evident that Carpenter's .specimen is very close to that just described, differing 
chiefly in the larger size, and in certain features such as an increased number of cirrus seg- 
ments and a relatively lesser length of the longer proximal cirrus segments, which are usually 
correlated with increased size. The apparent difterence in the number of the cirrus sockets may 
or may not be real, on account of the indistinctness of the drawing. It seems reasonable, 
therefore to refer the "Siboga ' specimen to the same species for which the name difficilis is 
available. 
With the arm structure of the Atlantic type [Neocomatella) this species possesses a 
very anomalous centrodorsal which is circular, and has the second row of cirrus sockets below 
the first instead of alternating with it as in all of the other genera of the Co master idae. 
It appears most logical, therefore, to erect for the reception of this species a new genus, 
Palacoconiatcl/a, most nearly related to the Atlantic Xeocoviatella, but diftering markedly in 
its curious centrodorsal. Whether this dispo.sition is the correct one must be left for future 
investig-ation to determine. 
& 
Capillaster .\. H. Clark. 
Key to the Species of the Genus Capillaster. 
a^ Cirri absent ; centrodorsal reduced to a small stellate plate lying within the radial circlet 
(BorneoandtheChinaSea) iiiacrobrachius 
?IBOG.\-EXI'KmTIi; .XI-Il/'. 2 
