216 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. XXXIy. 
posterior faces are almost at right angles, the opposed syzygial faces 
being practically round; next four joints similar to the second brach- 
ial; the joints from the second to the ninth brachial are rather dis- 
proportionately large, and very strongly tubercular; the following 
joints are wedge-shaped, smooth, nearly twice as broad as long, soon 
becoming rather more obliquely wedge-shaped, or practically triangu- 
lar, about as long as broad, and distally wedge-shaped again and 
much longer than broad, as much as four or five times as long as 
broad on the terminal joints. ‘The arms appear to have been between 
200 mm. and 250 mm. long. Syzygia occur between the fourth and 
fifth brachials, again between the ninth and tenth, and then at in- 
tervals of two to four (usually three or four) bifascial articulations. 
The first pinnule is on the second brachial; the genital pinnules 
have short round genital glands. 
Locality.—Albatross Station No. 4157; center of Bird Island 
bearing S. 77° 30’ K.; 11.1 miles distance; 762-1,000 fathoms; white 
mud, foraminifera, and rocks. 
One specimen, badly broken. 
Type.—Cat. No. 22682, U.S.N.M. 
Remarks:—Decametrocrinus rugosus is readily distinguishable from 
the other species of the genus by its large size and swollen and 
strongly tubercular lower brachials, as well as by its low centro-dorsal 
bearing a very large number of cirri, and having a large bare polar 
area. 
The genus Decametrocrinus appears to be of very general occur- 
rence in the Pacific and Southern oceans; first discovered by the 
Challenger near the Crozet Islands, it was again taken southwest of 
Melbourne, Victoria, and later in the Meangis Islands, northeast of 
New Zealand. The specimens from the two first localities were re- 
ferred by Doctor Carpenter to the same species, abyssorum, while 
those from the last were considered to be distinct, and were called 
narest. In 1906 the Albatross dredged a fine species off southwestern 
Japan which was described in the following year under the name of 
borealis. In depth, abyssorum ranges from 1,600 to 1,800 fathoms, 
naresi was found at 500 fathoms, and borealis at 361 fathoms, while 
rugosus was dredged somewhere between 762 and 1,000 fathoms, the 
bottom having receded during the haul. 
It is of course impossible to tell whether the 9-rayed character of 
the type of this species is constant, although externally no difference 
whatever is visible between the various rays. Doctor Carpenter .has 
shown in the case of Decametrocrinus abyssorum that the species is 
10-rayed from the radials outward, the basal star being 5-rayed as 
usual, thus suggesting that in the present specimen one of the rays 
has been omitted; it is necessary to be cautious, however, and not 
accept that conclusion hastily, in view of the recent discovery of a 
