110 BRISINGIDAE. 



Examination of the rays shows that there is no evidence of a syzygy at the 

 base; all of them are still attached to the disk, though broken at a greater or 

 less distance from it. The arrangement of marginal, adambulacral, and oral 

 plates about the mouth seems to be hke that of Freyellidea microplax, the geno- 

 type. There is a single genital gland on each side of the swollen area at base of 

 ray. The combination of characters which serves to separate this species from 

 all those previously known Ues in the very long, slender arms, the unusually 

 short inferomarginal and adambulacral spines, and the extraordinary oral 

 spinelets. 



Freyellidea octoradiata,' sp. nov. 

 Plate 6, fig. 1, 2. 



Rays 8. Disk 16 mm. across. Rays about 185 mm. long or perhaps more 

 (the tips are missing). R = about 12d. Disk high and slightly tumid, closely 

 covered with thick overlapping plates, a milhmeter across, more or less; in each 

 interradius, the large interradial plate is conspicuous, occupying the whole side 

 of the disk in those areas ; interradial plates smooth and bare, but all other disk- 

 plates with several (usually three or four) small, slender spines and rarely one 

 or two pedicellariae; the latter are nearly always on plates near arm-bases; 

 spinelets about .50 mm. long, with blunt and often shghtly swollen tips. Rays 

 rather stout, about 5.5 mm. wide at base and 3 mm. wide near middle; genital 

 area about 35 nmi. long and 8 mm. wide, where widest. Basal fourth of ray 

 more or less covered with spiniferous plates, similar to those of the disk but larger 

 and carrying more spinelets and pedicellariae; as far out as the genital area 

 extends, these plates are close together and cover the region completely but 

 beyond that point they become more and more separated, fewer in number 

 and smaller in size, until they finally disappear as very minute fragments carry- 

 ing a single pediceUaria; on the genital area the plates are, as a rule, much wider 

 than long, and the largest exceed 2 mm. in breadth; near tip, pediceUariae- 

 covered skin clothes dorsal and lateral parts of ray. 



Adambulacral plates rather short and stout, nearly cyUndi-ical; tliickness 

 more than half length; inner, aboral peak present but slender; armature as 

 usual in the genus; a short spinelet on the peak, extending across furrow and 

 carrying small pedicellariae; and a large actinal spinelet, the tubercle of which 

 occupies a large part of distal haK of plate ; near base of arm, these actinal spine- 

 lets are very stout with enormously widened flat, dentate tips, as in F. insignis 



' octoradialv^ = having eight rays, in reference to the unusually small number of arms. 



