72 THE ECHINODERMS OF TORRES STRAIT. 
scribed and made up of a few species, characteristic of the Indo-Pacific region, but appa- 
rently extending to the west coast of tropical America. These species are easily recognized 
in life by the slimy skin which covers the body; in dried material this becomes so thin and 
tightly drawn that the outlines of the skeletal plates show more or less distinctly. Save 
for this skin and the accompanying lack of granules and tubercles, the genus is very close 
to Ophidiaster. The species are distinguished from each other by the character of the adam- 
bulacral armature, by the relative proportions of the disk and rays, and by the color. The 
last seems to be a fairly constant and useful character, since dried specimens retain quite 
well the general tint of life. 
I doubt if the presence or absence of pedicellariz can be relied on without a good deal 
of care. The type of speciosus had the skin ‘‘richly beset”? with pedicellarie, while the 
Museum of Comparative Zoélogy specimen from the Philippines has only about 30 and my 
large one from Mer has none at all, or possibly the remains of one or two. Perhaps the 
development of the skin may offset the number of pedicellariz, increased thickening of the 
skin tending to eliminate these little organs. 
One of Peter’s original species, coriaceus, has been fully described and figured by de 
Loriol in his invaluable work on the sea-stars of Mauritius, and the same monograph 
reveals equally well the distinguishing characters of Gray’s species, leachii, from which 
I am unable to distinguish Peter’s second species, glaber. The species described by von 
Martens in 1866, speciosus, is a very well-marked one, and the same is true of Fisher’s 
callipeplus described in 1906. Verrill’s Lepidaster teres does not seem to have been met 
with since its original description, but the name Lepidaster was preoccupied and in any 
case seems to be synonymous with Lezaster; the species teres seems valid beyond doubt. 
Fisher’s recently described species analogus completes the list of known species in the genus. 
A specimen in the Museum of Comparative Zodélogy collection from the Hawaiian Islands 
represents an undescribed species. 
Key to the Species of Leiaster. 
Furrow spines of adambulacral armature 3 or 4 to a plate, with a more or less conspicuous longitudinal 
groove on the inner face. 
R about 6 br; no pedicellariw; abactinal papule not in well-defined areas...................-005- coriaceus 
R about 8-9 br ; pedicellarize numerous; abactinal papule in definitely circumscribed areas...... .. analogus 
Furrow spines not grooved on inner surface, or in very large specimens, slightly so on basal half. 
Furrow spines 3 to a plate; no pedicellari. 
Rays slender, tapering; middle furrow spine usually longest; skin soft and thin; color in life 
tdi). SEA RBIS ena eG ROI IoGae ap ol coms Rniters omen reac bc leres 
Rays short, stout, not tapering; furrow spines equal; skin thick, tough, smooth; color in 
life deep maroon-purple; tube-feet deep yellow...............0.00000eeeee sees callipeplus 
Iurrow spines 2 to a plate, rarely 3 on individual plates. 
Furrow spines long and slender, the length twice the width of a pair or more; color in life, or 
dry, red, more or less bright crimson, in very large specimens sometimes nearly 
black, when dry. 
Riabouts0—iliby-usuallyznojpedicellariscmaaseroncs aeeceke so esc eee eee eeee leachit 
Riaboutis—8 brsepedicellarism present iep-seet acetate reconvene eerrei casino eects speciosus 
Turrow spines short and wide, the length about equal to width of a pair, or a little more; 
color (dry) dull purplish-gray (probably purple in life)......................-- brevispinus 
Leiaster coriaceus. 
Peters. 1852. Monatsb. d. k. Preuss. Akad. Wiss. Berlin, p. 177.—De Loriol. 1885. Mem. Soc. Phys. Hist. 
Nat. Genéve, 29, No. 4, p. 37; pl. xiii, figs. 2-3d. 
The excellent account of this species given by de Loriol makes it possible to recognize 
it easily. It is known only from Kwerimba Island, Mozambique; Zanzibar; Wasin, B. E. A., 
and Mauritius. It reaches a large size, R = 150 mm., and when adult is covered by a notably 
thick, coriaceous skin. The color in life is not known, but in dry specimens is deep purplish 
or greenish brown, more or less dull orange on the lower side according to de Loriol. 
