MUSEUM OF COMPARATIVE ZOOLOGY, 139 
Ophiacantha rosea sp. nov. 
Plate X. Figs. 267, 268. 
Special Marks. — Disk-seales and radial shields hidden by a thick skin, 
which is elosely beset with very short, stout spines, which sometimes are no 
higher than grains. Eleven arm-spines, slightly rough under microscope. 
Description of an Individual (Station 308). —Diameter of disk 17 mm. Length 
of arm, 68 mm. Width of arms without spines 4.5 mm. Mouth-papille 
irregular ; there are usually five on the inner part of the angle, flattened and 
blunt ; and outside these, near end of mouth-slit, a group of from three to six 
irregular papille, short and flattened. Eight or nine teeth, shaped like blunt 
spear-heads. Mouth-shields and side mouth-shields closely joined and covered 
with thick skin, so that their outlines are not clear. Under arm-plates shield- 
shaped, with an angle within, a curve without, and re-entering curves on the 
lateral sides opposite the large tentacle-scales, Upper arm-plates with distinct 
outlines, broad fan-shaped, with a rounded or very obtuse angle inward. Side 
arm-plates, near base of arm, barely meeting above and below, and having a 
narrow projecting spine-ridge. Disk puffed, densely and evenly beset, with 
very short, stout, conical spines, which to the naked eye seem nearly like 
large grains ; scales and radial shields entirely covered. Eleven stout, blunt, 
‘regular, cylindrical arm-spines, which, under the microscope, are slightly rough. 
Lengths to that of an arm-joint 3.5, 4.7, 4, 3.8, 3.8, 2.8, 2.5, 2.5, 2.5, 1.2. .8 : 
1.3. One very large, thick, pointed tentacle-seale, over 1 mm. long. Color 
in alcohol, pale rose-pink above ; below yellowish. 
Specimen from the distant station. 145 differed only in having larger spines 
on the disk. A young one, with a disk of 7 mm. had onlv seven mouth- 
papilleo to each angle ; the additional papille at the outer end of mouth-slit had 
not yet appeared ; the disk-spines were forked and thorny, and the eight arm- 
spines were rough and almost thorny. 
Station 145, 310 fathoms, 8 specimens. Station 308, 175 fathoms, 12 + 
specimens. Station 236, 420 — 775 fathoms, 1 specimen. 
Ophiacantha imago sp. nov. 
Plate X. Figs. 275, 276. 
Special Marks, — Disk regularly set with small, short, thick stumps, each 
bearing a crown of blunt thorns; tentacle-scales small and pointed ; six short, 
opaque, cylindrical, scarcely thorny arm-spines, 
Description of an Individual (Kerguelen Islands). — Diameter of disk 8 mm. 
Length of arm 37 mm. Width of arm without spines 1.6 mm. Seven short, 
stout, blunt, close-set mouth-papille ; the innermost are a little the largest. 
Four flat, rather thick teeth, all squarish, except uppermost one, which is 
pointed. Mouth-shields small, of a rounded diamond-shape. Side mouth- 
shields short, wide, slightly curved, not meeting within. They and the mouth- 
