NO. 1615. ON A COLLECTION OF FEATHER STARS—OLARK. | sleles 
THALASSOMETRA KOMACHI, new species. 
The centro-dorsal is bluntly conical or short-columnar, the cirrus 
sockets closely crowded and arranged roughly in three columns in 
each radial area, two to a column; the bare polar area is granulose. 
The cirri are tweaty-five in number with forty to fifty-five joints, 
40 mm. long for the longer, 25 mm. for the shorter, basally slender 
and rounded, becoming much compressed and broad distally; the first 
four or five joints are about twice as broad as long; the next joint 1s 
squarish ; the next is about twice as long as its proximal diameter, de- 
creasing in diameter distally; the cirrus decreases in diameter at this 
point, the elongated transition joint being dull and dark like the pre- 
ceding in its anterior two-thirds, and highly polished like the succeed- 
ing in its distal third; the joints following the transition joint are ap- 
proximately squarish (the first being usually longer than broad), 
gradually becoming shorter and very short distally; at about the 
fourth joint beyond the transition the distal dorsal edge begins to pro- 
ject, soon becoming a deep dorsal spine, which arises from the whole 
of the dorsal border; the dorsal spines on the terminal joints decrease 
in height; the opposing spine is short and blunt, terminally situated, 
not reaching half the breadth of the penultimate joint in height; the 
terminal claw is stout and moderately curved, rather longer than 
the penultimate joint. 
The disk is scantily plated, except along the ambulacra, but the 
brachial and pinnule ambulacra are well plated. The sacculi are 
abundant on the brachial and pinnule ambulacra. 
The ends of the basal rays are visible as prominent, though small, 
tubercles in the angles of the calyx; the radials have a strongly 
curved distal border, not visible in the median line, but extending 
far up in the angles of the calyx and surrounding the ends of the 
basal rays, reaching as high as the lateral angles of the costal axil- 
—laries; the first costals are laterally concealed by the interradial an- 
terior extension of the radials and are visible as a triangle (apex 
downward) in the median line, the edges everted and roughened; the 
costal axillary is over twice as broad as long, rhombic, rising to a 
low tubercle with the first costal, the edges all around everted and 
roughened, the dorsal surface (as in the first costal) perfectly smooth; 
the distichals are 2, present on all the arms, resembling the costals; 
there are no palmars. There are twenty arms, 125 mm. long; the 
first brachial is wedge-shaped, the longer side out; the second brachial 
is nearly twice as large, but similar; the following to about the tenth 
are oblong, about twice as broad as long, soon becoming triangular, 
broader than long, gradually becoming as long as broad, and distally 
wedge-shaped again and more or less elongate. The oblong joints 
in the lower part of the arm have both the anterior and posterior edges 
