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The mouth-angles are covered with even smaller scales; each 
carries near its apex several long conical spines, which are not 
confined to the apex, but extend along the sides of the mouth-angles, 
and also within the buccal cavity, in two or three tiers, so as to appear 
almost like buccal or oral papille. They are more numerous and 
more slender than the tooth papillz of Astrotoma agassizii Lyman. 
A small oval madreporite lies at the edge of the horizontal cir- 
cumoral region, just below the ridge or fold connecting two neigh- 
bouring arms, and which separates the intergenital area from the oral 
area. It measures 1°5mm. in length which is horizontal or tan- 
gential, and 1 mm. in length which is vertical or radial. The genital 
clefts are 4 mm. in length—two in each interbrachial space. 
The arms are high, strongly arched abactinally and flattened 
below, tapering gradually; and the ends are coiled, to a greater 
or less degree, in all the specimens. The sides and upper surface 
are covered with granulated scales, and in the dried specimens the skin 
is depressed between the vertebral ossicles, so that the arm appears 
segmented—that is, it is surrounded by narrow grooves alternating 
with broader raised areas: in the grooves the scales are not per- 
-ceptibly smaller than elsewhere. On each side of the arm, on each of 
the raised areas, there are about twelve groups of minute glassy hook- 
lets, forming an interrupted ring round the lateral and upper surfaces 
of the arm; each group is borne on a flattish plate, a little sunken, 
‘surrounded by a more or less evident circle of the larger granules of 
the skin. 
The under - surface of the arm is covered by uniform rounded 
granules, rather larger than those on the under-surface of the disc, 
but smaller than those on the sides of the arm. Each “ segment” 
of the arm carries 8-10 short, cylindrical, blunt spines, terminating 
in a tuft of glassy spicules, so that the tips are distinctly rough. 
At about three-quarters of the length of the arm they begin to 
-decrease in number, till only 1 or 2 long, slender, clawlike spines re- 
main: this reduction is effected by the disappearance of the spines 
outside or above the pore. 
It is clear that these claws, as well as the roughened tips of the 
spine, serve admirably for grasping objects round which the arms 
may be coiled; and it happens that in most of the specimens these 
hooks have been broken away on removing the animals from the 
net in which they were captured. These “arm spines” or “ tentacle 
spines’ are set on a granulated ridge. 
The tentacle pore is on a level with the third spine from below. 
so that there are from 5~7 spines above, or outside, the pore. The 
first tentacle pore, situated on the disc, is without a spine; the 
second, which is on the base of the arm, just where it jois the disc, 
is provided with 3 or 4 spines ; the third pore has 5 spines on a ridge; 
the next. 6 or 7, and the full number is soon attained. 
Locality.—East coast of Otago. 
