1062 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
spine. The plates are also surrounded by a series of granules, similar to but larger than those of the 
superomarginals. Occasionally this series is incompletely double, especially along the lower margin. 
Adambulacral plates are considerably broader than long, and the actinal surface is slightly raised 
above the level furrow margin (i. e., when animal is viewed from below). Armature as follows: 
(1) A furrow comb of 9 (or 8) spines, the lateral members of which are usually shorter than the other 
7, which are subequal,' parallel, about as long as the plate, round-tipped, slightly compressed, and 
untapered. The adoral end of each series overlies the aboral end of the adjacent series toward mouth. 
(2) On the actinal surface 2 thick, robust, cylindrical, blunt or truncate spines disposed in a transverse 
row. These may be very slightly tapering, and are about as long as the width of a plate. Margin of 
plate is surrounded by a single series of large, bead-like granules, and there are also 2 or 3 granules on 
the general surface of the plate. 
Mouth plates are not prominent, but of fair size, elongate. The united pair form a regular pro- 
jecting angle, with a long free furrow edge. Each plate is a low isosceles triangle in shape, the base 
to the median suture. Armature as follows: (1) A furrow series of 9 spines, the outer 6 of which are 
like those of the adambulacral plates and increase slightly in length toward the inner angle. The 3 
inner spines are much larger and heavier, and increase in size toward the inner angle, the innermost 
tooth being blunt, heavy, and flattened on the actinal surface. There are thus 6 teeth at each 
mouth angle. (2) On the actinal surface one heavy spine, like the corresponding spine of adambu- 
lacrals, situated at about the center of plate; and a much smaller spine standing in line with it, toward 
the inner angle. The latter varies in size. Several large flattened granules occur near this spine. 
Along the edge adjacent to first adambulacral, and on outer half of median suture margin (i. e., behind 
the big spine) are numerous (12 to 14) large irregular granules in an irregular series. 
The actinal interradial areas extend as far as the fourth inferomarginal. They are paved with 
large 4 to 5 sided plates, which are bordered by a row of prominent bead-like granules. Those plates 
adjacent to the adambulacrals are slightly convex, and as far as the third inferomarginal each bears a 
large 2-jawed pedicellaria, set in a special depression. Each jaw is broadly spatulate and rounded at 
the tip and when the pedicellaria is open fits into a special depression of the plate. Two or 3 other 
plates in the interradial region also bear a single pedicellaria, so that there are 19 or 20 pedicellariae 
to each actinal interradial area. The majority of other plates bear 1 to 6 bead-like granules on the 
surface, in addition to the peripheral series, and these are usually clustered to one side, leaving most 
of the plate smooth. 
Tube feet have large sucking disks. Ambulacral furrow is very narrow, entirely closed over by 
the furrow armature. Anal aperture is subcentral, very small. 
Madreporic body is flat, circular, larger than any abactinal plates; situated midway between 
center of disk and inner edge of superomarginals. 
Color in life: Abactinal area between chocolate color and Mars brown; superomarginal plates 
chocolate; spaces between abactinal plates in central portion of disk much darker, showing the plates 
in relief. Actinal surface buff pink, excepting large spines and adambulacral plates, which are cream 
color. Color in alcohol, dull brown, lighter beneath. 
Locality: Station 4100, Pailolo Channel, between Maui and Molokai Islands, 130 to 151 fathoms, 
coral sand, shells, foraminifera; bottom temperature, 61°. One specimen, type no. 21167, U. S. 
National Museum. 
This remarkably beautiful starfish evidently belongs to the genus Calliaster, although the other 2 
known species are devoid of pedicellarise. This feature alone will serve to distinguish the present 
form. It is also characterized by the following details of structure: The rays are longer and narrower 
than in the other species, with several distal superomarginals in contact medially; abactinal spines 
are fewer; superomarginal spines fewer and larger; actinal adambulacral spines 2 and very large; 
furrow comb of 8 or 9 spines; no enlarged tubercle on actinal intermediate plates as in baccatus. 
There are numerous minor differences which are appreciated by a comparison of figures. Calliaster 
cMldreni comes from Japan, C. baccatus from Simon’s bay, Cape of Good Hope, 5 to 18 fathoms. 
Genus GILBERTASTER, new. 
Type Gilbertaster anacanthus, new species. 
Form stellate, with a broad, slightly convex disk and wide, rounded interbrachial arc. Marginal 
plates prominent. No spines on abactinal, marginal, or actinal plates. Pedicellarige very large and 
bivalved. 
