632 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 4S. 



dorsal side, and rather evenly and fully curved from the inner to the 

 outer margin, the lateral face being only a trifle narrower than the 

 dorsal. Plates 13 in type, increasing in size up to the third which 

 meets its fellow medially. This plate is shghtly longer than wide 

 (or the 2 dimensions subequal) as seen from above, and thence the 

 plates are increasingly longer than wide. The first 3 plates are shorter 

 than the chord of the extreme width, however, and in the fourth the 

 length about equals chord of width. The plates are covered with 

 shghtly spaced, depressed, subspherical granules, subequal to those 

 occupying the center of the abactinal plates. Beyond the second 

 inferomarginal all are normally longer than wide, as seen from below. 

 A small entrenched 2- jawed pedicellaria is found on some of the 

 proximal plates of the type, but not in other specimens. 



ROSASTER MIMICUS, new species. 



Resembling somewhat R. hipunctus (Sladen), but differing in 

 having sharper rays, compacter paxillse with numerous crowded 

 central granules, more numerous, compressed, furrow spines (12 to 

 14), more numerous subambulacral spines and granules, and more 

 numerous oral spines. Form stellate with arcuate interbrachia and 

 gradually tapering rays; sides of ray and disk perpendicular with a 

 longitudinal depression; breadth of ray, measured at proximal suture 

 of first pair of superomarginals which meet medially equal to first 

 3h or 4 superomarginals measured on ambitus; abactinal plates 

 strongly tabulate on papular areas and with upward of 23 central and 

 25 peripheral granules on the radial series; abactinal, marginal, 

 actinal intermediate, and adambulacral pedicellarias ; subambulacral 

 armature a series of prismatic spines and 2 or 3 parallel series of 

 granules; furrow spines 12 to 14. R = 56 mm., r = 21 mm., R = 2.7 r 

 (cotype) ; in type R = probably 75 mm. and r = 23 mm. 



Type.— Cat. No. 30540, U.S.N.M. 



Type-locality. — Station 5281, between Lubang and Luzon (lat. 

 13° 52' 45" N.; long. 120° 25' E.), 201 fathoms, dark gray sand; 

 bottom temperature, 50.4° F. 



ROSASTER MAMILLATUS, new species. 



Differing from R. alexandri, and other small species, in having the 

 superomarginals beyond the third plate separated by a single series 

 of abactinal plates nearly to extremity of ray, and in the presence on 

 the distal marginal plates of a small central tubercular granule, larger 

 than any of the other granules. R = 21 mm., r = 7.5 mm., R = a little 

 less than 3 r; breadth of ray at mid-interbrachium, 7 mm. Supero- 

 marginals massive, tumid, 13 in number, and covered with roundish, 

 rather coarse, subtruncate, slightly spaced granules, the peripheral 

 being largest on the dorsal facet of plate; the 5 or 6 superomarginals 

 preceding the last with an enlarged, subcentral, tubercular granule; 



