NEW STAKF1SHKS FROM DEEP WATER OFF CALIFORNIA AND ALASKA. 807 



tipped, sharp-edged granules, larger than those of the outer series, which are very irregular in dis- 

 tribution, 8 or 9 in number, and similar to, but a trifle larger than the actinal intermediate granules; 

 there are sometimes 2 irregular rows of these smaller outer granules; al adoral end of inner actinal 

 series a pedicellaria with 2 broadly spatulate jaws, slightly larger than the granules of the series, 

 which the pedicellaria greatly resembles when the jaws are closed; at tip of "ray" -1 or 5 spinelets 

 in the furrow series, and on the actinal surface a blunt, prominent tubercle, surrounded bj several 

 granules, this tubercle grading into the granules of the inner actinal series. The pedicellaria persists 

 to within L' or .'! plates of the tip. 



Mouth plates triangular, with a longer furrow margin than the edge adjacent to first adambulacral ; 

 furrow series consisting of 11' or 13 spinelets similar in character to those of adambulacrals, hut increas- 

 ing in size toward inner angle, where there is an oblanceolate, blunt, flattened or compressed tooth, 

 the other spinelets square in section or slightly compressed; on actinal surface a linear series of low, 

 squarish granules adjacent to the median suture, several others along the aboral edge, and l' or :i inter- 

 mediate between the superficial and marginal series. 



Actinal interradial areas very extensive; intermediate plates quadrate, roundish, or irregular, 

 those adjacent to the adambulacrals much larger than any of the others, and usually oblong in shape, 

 the short end toward furrow; plates arranged in rows parallel to furrow, considerable irregularity 

 existing; plates covered with uniform, hemispherical, beadlike granules slightly spaced; pedicellaria' 

 .similar to those of adambulacral plates scattered here and there, especially near the furrow, hut their 

 numbers subject to great variation. 



Madreporic body irregular in outline, larger than any plates, situated A distance from center to 

 margin; slightly convex and the striations, of medium coarseness, radiating from the center, irregu- 

 larly. 



Color in life: Vermilion, yellowish on actinal surface. 



Locality: Type from station 4:)7s, off Point Loma, near San Diego, Cal., :57ti to ">94 fins., green mud 

 and sand. 



This is a variable species as regards the minor details of ornamentation and contourof body. The 

 younger specimens are not so noticeably thin and Hat, and the marginal plates are more normal. The 

 secondary abactinal plates are wanting in young specimens, and in examples :} the size of type vary 

 considerably in numbers. The pedicellaria; appear to be numerous on the abactinal surface of all the 

 specimens. 



This is in some respects a very abnormal Toxin, especially in the character of the abactinal (plates, 

 and in the presence of secondary smaller ossicles intercalated between the larger primary plates. The 

 small marginal plates give it a very peculiar appearance, and, combined with the thinness of the body. 

 form characters which will readily separate this species from any other now referred to the genus. 



I found a very flat Myzostoma I M. fisheri Wheeler) in an interradial portion of the coelomic cavity 

 of one specimen. 



Subfamily MEDIASTEKIN.E Verrill, 1899. 



Genus MEDIASTEE Stimpson. 



Mediaster Stimpson, Jour. Boston Sop. Nat. Hist.. I. lsr.7. 490, pi. 23, figs. 7-11 (.Mediaster sequalis Stimpson). 



Mediaster tenellus, new species. 



Rays 5. R = 58mm.; r = 19mm. R = 3r. Breadth of ray, between first and second superomar- 

 ginals, 20 mm.; at middle of ray, 7 or S mm. 



General form flattened; disk large; rays fairly long and slender, tapering abruptly at base, then 

 more gradually; interbrachial arcs very wide, and rounded; abactinal surface inflated on radial areas, 

 sunken on interradial areas, the rays especially being convex; actinal surface considerably inflated on 

 disk; marginal plates small, confined nearly to sides of body. 



Abactinal area covered with ornate, regularly spaced paxillse, largest in a regular median radial 

 series, decreasing thence toward tip of rays and margin of disk; paxillse of median radial series 

 elongated transversely, the others roundish, the former bearing on the periphery of the pedicel or 

 tabulum 15-17 prismatic, blunt spinelets, as long as or slightly longer than the lesser dimension of the 

 tabuluni ami decidedly longer than is usual in this genus; in the center 6 or 7 irregular, prismatic, 



