430 On new Genera and Species of Brisingide. 
Freyellidea microplax, sp. n. 
Diagnosis.—Rays 12, not deciduous, only moderately long, 
with a short, swollen genital region about 4 7 in length. 
Disk closely ‘covered with short spinelets, 4 or 5 to a plate ; 
genital region of ray covered with small, transversely oriented, 
elliptical, somewhat irregular plates bearing groups of 2 to 8 
small spinelets ; 19 or 20 plates can be counted across ray 
at widest part. Short lateral spine opposite alternate 
adambulacral plates. Adambulacral armature: Laboral furrow 
spinelet, and 1 subambulacral spine, with truncate enlarged 
tip at base of ray ; first adambulacral plates of adjacent rays 
not fused, the outer end of the mouth-plates intervening ; 
oral armature: 3 actinostomial spinelets and 1 short, sharp, 
suboral spine. R=170 4- mm., r=10 mm., R=17+4r; 
thickness of disk 4 mm.; width of ray at base 4°5 mm.; 
breadth of actinostome 13 mm. 
Type-locality. —‘ Albatross’ station 3342, off British 
Columbia (52° 39’ 30’’ N., 132° 38’ W.), 1588 nome grey 
ooze and coarse sand, bottom temperature 35°°3 Fahrenheit, 
ASTROCLES, gen. nov. 
Diagnosis.—As given in foregoing synopsis. 
This curious genus agrees with Freyellidea in its most 
important features—the absence of a proximal adambulacral 
syzygy, absence of marginal plates above the first few 
adambulacral plates, and the presence of only two gonads 
to each ray. The differential characters are given in the 
synopsis. The following species is the type of the genus. 
Astrocles actinodetus, sp. n. 
Diagnosis.—Rays 11, not very deciduous; disk fairly 
large, covered with circular plates bearing 1 to 3 spinelets ; 
genital region of ray 3°5 to 4 rin length, or about one-sixth 
total length of ray, and crossed by 25 to 27 pretty regular 
transverse arches of depressed, elliptical, crenulate plates 
covered with a felting of minute pedicellarie and bearing 
small spinelets in transverse series ; intervals between arches 
without plates or pedicellariz ; lateral spine opposite alternate 
adambulacrals, very slender and delicate; adambulacral 
armature consisting of 1 aboral furrow spinelet with tip 
greatly broadened and subtriangular in form, and 1 sub- 
ambulacral spine, those on proximal half or two-thirds of 
genital region with an enlarged bifid tip; mouth-plates with 
3 actinostomial spines, expanded, flattened, and more or less 
