series reaching a little over a fifth. The plates are closely covered with small granules immersed in membrane, the tips of the granules often protruding slightly from the membrane or visible yet covered by membrane. In the former case the granules appear to be embedded in a matrix. A majority of the plates bear 1, sometimes 2 or 3, small spatulate entrenched pedicellariae.

Adambulacral plates slightly longer than wide, with an angular furrow margin, the 2 facets of the apophysis being somewhat varable in length, but the distal always the longer and slightly concave as in Nymphaster. Spinelets proximally 10 to 12, distally 6 to 9, rather short, stout, round tipped or truncate, in a crowded series, the longest on the angle, and compressed in a plane transverse to the plate, the others gradually shortening slightly and with flat side to furrow. Actinal surface of plates slightly convex, covered with 20 to 35 granules immersed in membrane. Near or at the inner adoral corner of the plate there is usually a pedicellaria with 2 to 4 variable granuliform jaws. There is no enlarged subambulacral spine on the distal plates. On the outer part of the ray the apophyses of opposite plates tend to meet in the middle of the furrow and to segregate consecutive pairs of tube feet.

Mouth plates very slightly convex, coarsely granulate, the granules being conspicuous; marginal spinlets 16 to 19, robust, increasing in size toward the inner angle, where the spinelets are very strongly compressed, broad, and leaflike. The furrow surface of each plate has a shallow vertical depression for the first tube feet.

Madreporic body one-third minor radius from center; ridges coarse, radiating.

Anatomical notes.-Gonads are arranged in a short series nearly parallel with the radius and 7 or 8 mm. therefrom. There are 6 or 7 closely placed tufts in the series examined, and it extends only about 10 mm. The coelomic sacs leave a slight interradial area ventrally and adjacent to margin, lined with very fine fibrous tissue, which more or less occludes the cavity. Tube feet with conspicuous sucking disks.

Type.-Cat. No. 28659, U.S.N.M.

Type-locality.-Station 5655, Gulf of Boni, Celebes, 608 fathoms, gray mud, fine sand, bottom temperature 39.2° F.; 1 specimen.

Distribution.-East coast of Luzon, and the Gulf of Boni, Celebes, 565 to 608 fathoms, green or gray mud.

Specimens examined. In addition to type, a badly mutilated specimen from station 5460, Lagonoy Gulf, east coast of Luzon, 565 fathoms, green mud.

Remarks. This curious species is notable for the development of the superomarginal plates at the expense of the inferomarginals. The former define the ambitus, and when the specimen is viewed from

below the ventral surface of the superomarginals forms a narrow border outside the inferomarginals. The presence of a more or less pulpy membrane covering the granular investment suggests an alliance of this form with Anthenoides. An important difference is the fact that in Anthenoides and Stellaster the membrane covers the animal without reference to the underlying plates, while in Atelorias each plate is distinct, the membrane not overlying the sutures.

Family OREASTERIDAE Fisher.

Oreasteridae FISHER, 1911d, p. 18 (=Pentacerotidae, untenable).

Genus OREASTER Müller and Troschel.

Oreaster MÜLLER and TROSCHEL, 1842, p. 44.

Pentaceros SCHULZE, Betrachtung der versteinerten Seesterne u. ihrer Theile, 1760, p. 50 (not binomial). Many authors.

KEY TO SPECIES HEREIN RECORDED.

a'. No marginal spines or tubercles; a radial series of very large acorn-shaped tubercles, the primary radial the largest; tubercles with flat, polygonal, granules larger than the other abactinal granules, and usually with a subglobose or conical, bare, knob at summit. In addition to radial tubercles, others are sometimes present interradially------nodosus, p. 346. a Prominent distal superomarginal and inferomarginal spines, and usually a few small inferomarginal spines in interbrachia; abactinal spines very prominent, conical, heavy, and granular (the granules not larger than others), with a prominent bare conical sharp tip; these spines are slenderer and higher (as a rule) than those of nodosus and occur radially, interradially, and usually within apical area.... -alveolatus, p. 348.

OREASTER NODOSUS (Linnaeus).

Plate 102, fig. 2.

Asterias nodosa LINNAEUS, Syst. Nat., ed. 1758, p. 661.

Oreaster nodosus BELL, 1884, p. 70.-CLARK, 1908, p. 280.

Pentaceros turritus PERRIER, 1875, p. 240 (which see for earlier synonymy. Figured by Gray, 1866, pls. 9 and 10, under names Pentaceros modestus and P. franklinii).

Notes on Philippine specimens.-The specimens vary considerably in the number and form of the large acorn-shaped tubercles of the carinal ridge, as already recorded by Clark. In most cases the tubercles are higher than the breadth at base and are capped by a blunt or pointed tip free from granules. Seven specimens have the tubercle in the center of disk. The maximum number of tubercles is present in specimens from station 5254, where there are 60 in a typical specimen and 69 in another, having in addition to the above 69 dorsal tubercles about 28 smaller superomarginal ones. The tubercle is not always terminated by a blunt or short spine, which is lacking in most of the Pangasinan Island examples. In these the

tubercles are covered with granules, which are variable in size, sometimes smaller than at the base, sometimes larger. A few of the tubercles in these specimens may have a blunt spine. The largest primary radial tubercles may terminate in 2 or 3 points. The number of pedicellariae is very variable. They may be very numerous on the dorsal surface or fairly scarce. Their form is also variable; usually the abactinal pedicellariae have slender upright jaws, considerably longer than wide. But in examples from Burias Island the pedicellariae are few and low, with the jaws as low as or lower than broad.

The furrow spines vary from 6 to 8. The subambularcral spines are usually 3 in number, much heavier than the furrow spines, and grooved or eroded at the tip (as well as down the sides in many large examples). The subambulacral pedicellaria is adoral to the subambulacral spines and between them and the adoral furrow spine. Sometimes this pedicellaria is as long as the median furrow spines, but is ordinarily a little shorter.

One specimen has 4 normal rays and 2 short ones. A specimen from Burias Island has lost all the abactinal tubercles, the scars where they were broken off or torn out are very distinct. Other specimens have lost 1 or more tubercles by accident, the wound having healed.

The most curious variation is exhibited by a specimen from station 5254, which agrees with 2 other examples from that station in all essential respects except the possession of from 1 to 4 superomarginal tubercles on each side of the rays (28 in all). These tubercles are smaller than the dorsal ones. It is possible that this specimen is a hybrid of O. nodosus and O. alveolatus, a specimen of the latter having been taken in the same haul. The dorsal tubercles are quite typical of nodosus and not of alveolatus.

It is worthy of note that a series of very small intermarginal plates (4 to 6 to each interbrachium) is present, but completely hidden by granules (see Pentaceropsis).

Distribution.-Region of the Indian Ocean, East India Islands (north to Luzon), thence to New Caledonia, in the Pacific.

Specimens examined. Thirty-four, from the following localities: San Pascual, Burias Island (off Luzon), tide pool on sand, flat, 6 specimens.

Papatag Island, Tawi Tawi Group, Sulu Archipelago, shore, 3 specimens.

Tataan Pass, Simaluc Island, Tawi Tawi Group, shore, 1 specimen. Cagayan de Jolo, 1 specimen.

Pangasinan Island, Jolo, reef, 14 specimens.

Pandanon Island, between Cebu and Bohol, coral sand, 1 specimen.

Station 5254, Gulf of Davao, Mindanao, 21 fathoms, sand, coral, 3 specimens.

Philippine Islands, Dr. E. A. Mearns, 3 specimens.

OREASTER ALVEOLATUS (Perrier).

Plate 101, fig. 1.

Pentaceros alveolatus PERRIER, 1875, p. 243.-KOEHLER, 1910a, p. 95, pl. 10, fig. 1; pl. 14, fig. 7.

Oreaster alveolatus BELL, 1884, p. 73.

Notes on Philippine specimens.-In 2 specimens (stations 5254 and 5141) the spines are absent from the interradial region of the dorsal surface; in the others there are from 5 to 10 spines in each interbrachial area, in addition to those of the midradial line and apical area. The spines are for the most part very prominent, slenderer than the tubercles of O. nodosus, and upward of 20 mm. in length. The granules are absent, as a rule, from the tip, which is conical and sharp. Those covering the lower part of the spine are a little larger than the granules covering the plates, crowded, flat, and polygonal. In the largest example, having R=170 mm., 3 of the 5 primary radial spines are double, and there are 3 spines within the apical area. In all the specimens the interbrachial inferomarginal spines are poorly developed, and in an example from station 5141 there is only a single small tubercle in 2 interradii, but 2 to 4 prominent inferomarginal spines at the end of the ray. The superomarginal spines are usually very prominent, especially in a specimen from station 5146, where there are upward of 14 on either side of each ray, most of them ending in a bare, conical sharp point. In 2 interbrachia there is a single superomarginal spine. This specimen has 3 to 5 interbrachial inferomarginal small, blunt, tuberculate spines. The trabeculae separating the papular areas are well marked, except sometimes the transverse ones of the series of areas just above the superomarginals, where the areas may be partly confluent. Along either side of the ray, which is naturally high, are 3 well-marked lines of papular areas, with 1 or 2 additional for a very short distance at the base of ray. The uppermost series may be subdivided into 2 series of alternating triangular areas, while the areas of the 2 lower series are rectangular, elliptical, or irregular.

In addition to long, low, bivalved, slit-like pedicellariae on the trabeculae, there is a very variable number of small upright forceps pedicellariae on the papular areas. The jaws of these vary in height from about the length of the surrounding granules (Jolo) which are subconical or convex, to twice the length (stations 5149, 5254) or

A specimen from station 5141 has numerous much larger pedicellariae with slender, curved, spatulate jaws about 4 times as high as the granules. These are on the papular areas while the usual slitlike form occupies the trabeculae.

The adambulacral armature does not agree with the description of Perrier. There as 7 or 8 furrow spines (5 or 6 in the type), but in a specimen from station 5254, 9 or 10. Subambulacral spines 2 or 3, heavy, with wrinkled tips. External to these is a second series of 2 or 3 shorter spines, or rather enlarged granules, likewise with slightly wrinkled tips. Perrier speaks of but 1 series of subambulacral spines. These specimens are really triplacanthid according to Bell's classification. The granules of the actinal surface are very unequal in size, some of them being fairly tuberculate.

A young example with R=23 mm. has developed low primary radial spines, several superomarginal spines, and upward of 5 superomarginal spines at the end of ray only. The disk is low and the general appearance goniasterid. A slightly larger specimen has developed a few additional lophial spines. Furrow spines 5 or 6; usually 2 subambulacral spines.

Four to 6 small intermarginal plates are present in each interbrachium. The largest can sometimes be detected, but the smallest are obscured by the granules.

Type-locality.-New Caledonia.

Distribution.-New Caledonia and Philippine Islands.

Specimens examined.-Nine:

Jolo Market, Jolo; 1 specimen.

Station 5136, off Jolo Light, Jolo, 22 fathoms, sand, shells; 1 specimen.

Station 5141, off Jolo Light, Jolo, 29 fathoms, coral sand; 1 specimen.

Station 5146, off Sulade Island, vicinity of Jolo, 24 fathoms, coral sand, shells; 1 specimen.

Station 5149, near Sirun Island, vicinity of Siasi, Sulu Archipelago, 10 fathoms, coral, shells; 1 specimen.

Station 5165, near Observation Island, Tawi Tawi Group, Sulu Archipelago, 9 fathoms, coral; 1 specimen (young).

Station 5253, off Linao Point, Gulf of Davao, Mindanao, 28 fathoms coral; 1 specimen (young).

Station 5254, same locality and depth; 1 specimen.

Mansalay Bay, southeast Mindoro, 5 to 10 fathoms, 1 young. Remarks. This species seems to have been known previously only from New Caledonia, where it has a near relative, O. novae-caledoniae (Koehler). It is nearest O. linckii, to which none of the