56 BULLETIN 76, UNITED STATES NATIONAL MUSEUM 



is an ampulla. Viewed from above, the buttresses plus the enlarged ambulacral 

 knobs form a raised pentagonal frame for the subcircular actinostome. The ambula- 

 cral ridge is permanently bent upward at the base, which causes the actinostome from 

 the outside to appear sunken. Ampullae really single, somewhat triangular in form 

 when inflated; when deflated there appears to be an indication of an incipient external 

 lobe; no Polian vesicles; two Tiedemann organs. The superambulacral ossicles are 

 slender and one to each ambulacral plate; two or three consecutive plates converge 

 to attach themselves to the lower ends of the second series of actinolateral plates. 



Type.— Cat. No. 37041, U.S.N.M. 



Type-locality.— Station 2890, off Oregon (43° 46' N., 124° 57' W.); 277 fathoms, 

 gray sand; bottom temperature, 42.2° F.; six specimens. 



Distribution.— Known from off Oregon and central California; 277 to 296 

 fathoms, gray sand; 41.8° to 42.2° F. 



Specimens examined. — One hundred sixty-eight, in addition to six from type- 

 locality. 



Station 3112, off Pigeon Point, north of Monterey Bay, Calif. (37° 08' N., 122° 

 47'W.); 296 fathoms, fine gray sand; bottom temperature, 41.8° F.; 179 specimens. 



Station 3145, off San Luis Obispo County, Calif., 35° 14' N., 121° 07' W.; 252 

 fathoms, green mud; bottom temperature, 43.2° F., nine specimens; bottle broken 

 during earthquake, 1906; locality reasonably certain; specimens not typical, inter- 

 mediate with platyacanthum. 



Family ASTERIIDAE Gray, emended 



Asteriidae Gray, Ann. Mag. Nat. Hist., vol. 6, 1840, p. 178. 



A polyphyletic aggregation of genera, some probably very ancient, which have 

 been placed for convenience under the aegis of Asterias. They have the common 

 characteristic of not belonging in the other families of Asteriadina. (See synopsis, 

 p. 4.) 



SYNOPSIS OF THE SUBFAMILIES OF ASTERIIDAE 



o 1 . No marked adoral carina, the first pair of postoral adambulacral plates separated interradially 

 (or in contact only along the adoral part of the interradial margin) in combination with 

 inferomarginals having never more than one prominent spine. Rays five or six; skeleton 

 an open network composed of mostly small cruciform or trilobate plates; spinelets small; 

 crossed pedicellariae scattered, never in circlets about spinelets; straight pedicellariae 

 present; no adambulacral spine pedicellariae; tube-feet biserial or quadriserial on proximal 



part of ray Pedicellasterinae Fisher. 



a 1 . An adoral carina; i. e., at least one, but usually several, pairs of postoral adambulacral plates 

 in contact by their interradial margins; tube-feet quadriserial at least proximally. 

 b 1 . Adambulacral spines without attached pedicellariae, singly or in clusters, although these 

 may occur on the oral spines. 

 c 1 . Primary apical plates conspicuously enlarged; abactinal and marginal plates subhexagonal, 

 closely imbricated in seven regular longiseries (resembling Zoroaster), sparsely granu- 

 lated; actinal plates with short spinelets Neomor-phasterinae Fisher. 



c'. Primary apical plates not conspicuously enlarged; rays not resembling those of Zoroaster. 

 d l . Rays numerous, long, slender, in combination with only one inferomarginal spine (on 

 each plate) carrying a prominent wreath of crossed pedicellariae. No actinal 

 plates; abactinal skeleton either very open with large squarish meshes or else 

 abortive with scattered independent plates; crossed pedicellariae in abactinal spinal 

 wreaths or thick ruffs Labidiaslerinae Verrill. 



