70 THE ECHINODERMS OF TORRES STRAIT. 
in the living specimen, the rays were more rounded on the sides. Abactinal surface of 
disk covered by 35 to 40 plates of which one at center is largest; this central plate is kidney- 
shaped with its long axis in the interradial line of the madreporite and at its concave side 
lies the anus, surrounded by 8 to 10 granules; 5 large interradial plates can be distinguished, 
the largest occupied almost wholly by the elliptical madreporite, whose surface is marked 
by only 7 radiating and more or less angular or curved furrows; the madreporite is half- 
way between center and margin of disk; 5 large radial plates, about as large as the inter- 
radial but more nearly circular, lie at the base of each ray and can not be distinguished 
by any obvious character from the plates which cover the abactinal surface of the rays. 
The remaining plates on the disk are much smaller and show no particular regularity of 
arrangement. All the disk plates are bare and more or less markedly convex; they are 
separated, or at least surrounded, by relatively coarse granules of various shapes and sizes. 
The abactinal surface of each ray is covered by the big superomarginal plates, 14 or 15 on 
each side and a single median series of 12 or 13 similar plates; none of these plates is cir- 
cular or squarish, but otherwise they show much diversity of form; typically they are much 
longer than wide and the long axis lies obliquely to the long axis of the ray; all are bare 
and more or less strongly convex, especially distally; the median series is not always as 
perfectly regular as the marginals, a smaller plate occasionally being intercalated. At 
the base of the ray there are some half dozen very small plates intercalated between the 
median and marginal series, but they are so much smaller than the others that they might 
be easily overlooked. 
It is unfortunate that the colored figure (pl. 7, fig. 2), which was made primarily to 
show colors in life, shows the upper ends of the inferomarginal series so that there seem to 
be 5 series of plates on the upper side of the ray. In the dry specimen the inferomarginals 
do not show from above. Granules of relatively considerable size occur between or around 
all the plates but they are not at all conspicuous or numerous; they are not often present 
between the plates of the median series, but between each two superomarginals is a series 
of 3 to 7, often elongated, sometimes more than twice as long as wide. The terminal plate 
of each ray is very large, swollen, hemispherical, twice as large as the largest marginal. 
Papule large and always isolated, about 20 on the disk and 25 on each ray; on the rays 
they form an imperfect series on each side, with a papula between the inner ends of nearly 
every 2 marginal plates; the openings are surrounded by about 3 granules or granules and 
a pedicellaria. Pedicellariee fairly common, 4 or 5 on the disk and 7 to 10 on each ray; 
they are low, bivalved, much larger than one of the granules and conspicuous in the dry 
specimen because of their pure white color. One is rarely on an abactinal plate; as a rule 
they are between plates among the granules. 
The inferomarginal series consists of 14 plates, the most proximal narrow and nearly 
vertical in position, so that it is 3 times as high as it is wide, but the plates gradually widen 
and take on a horizontal position so that the terminal one is twice as long as high; all are 
convex, but the last 3 to 5 tend to develop a tubercle near the center. At the base of the 
ray between the two marginal series are about 4 well-developed intermarginal plates; 
on the sides of the ray between the 2 marginal series are granules, 7 to 11 papule and 3 to 6 
pedicellariz. Inferomarginal plates separated (?) from each other by imperfect series of 
minute granules. Actinolateral plates about 13, in a conspicuous single series, which, at 
least proximally, correspond to the inferomarginals; distally the actinolaterals decrease 
greatly in size and the series does not quite reach the tip of the ray; there is a small inter- 
radial plate back of the orals, from either side of which an actinolateral series starts. All 
these plates are separated (superficially, of course) from each other, and from the infero- 
marginals, adambulacrals, and orals by granules, and here and there is a pedicellaria. 
A series of about 10 papulz runs along each side of the ray, one between the lower or inner 
ends of every 2 inferomarginals until about the eleventh. Adambulacral plates about 28, 
