4 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
sparsely distributed over shell surface; long, tapered hairs, as well as 
flared hairs on lateral surface of shell near outer margins, appear to 
protrude from false radial pore canals. About 11 long, bifurcating 
hairs bearing secondary hairs form row on inner lamella behind 
rostrum (figs. 1p, £); a small tapered hair, immediately below rostral 
incisure, is followed by a space and then a bare hair on left valve, and 
three bare and two brushlike hairs on right valve; these are followed 
by a space and then 16 or 17 brushlike hairs, all having bases on or 
near list (figs. 1a, H); short, bare hairs are distributed between list 
and inner margin of posterior and posteroventral parts of inner 
lamella (figs. 2a, B). 
Dimensions.—Length 1.37 mm., height 0.92 mm. 
First antenna (fig. 34): First joint elongate with clusters of fine 
hairs on broad surface. Second joint about three-fourths length of 
first, with numerous fine hairs; annulated bristle near middle of dorsal 
margin; slightly shorter bristle near anteroventral corner; short bristle 
near middle of distal margin. Third joint about one-half length of 
second; anterodorsal margin with short, bare bristle and long plumose 
bristle; anteroventral margin with bare bristle about length of third 
joint; short spines on ventral margin. Fourth joint about twice 
length of third; anterodorsal margin with two long, slender bristles 
about length of joint, both bristles with short, fine hairs; anteroventral 
corner with about four bristles, two long, two short; ventral margin 
with short spines. Fifth joint slightly longer than third; anterodorsal 
corner bears slender bristle with short hairs. End joint (or joints) 
fused, with numerous bristles (ventral bristle may be attached to end 
of fifth joint). 
Second antenna (figs. 3B—E): Exopodite: first joint about twice 
leneth of following joints combined ; second to ninth joints trapezoidal, 
each joint smaller than preceding, all without basal spines; mediodistal 
margin of second to eighth joints with comb of slender spines; second 
to ninth joints with long bristles; bristles on second and third joints 
without natatory hairs, bristles on fourth to ninth joints with natatory 
hairs; bristles on second and third joints with short marginal spines, 
some spines also observed on bristles of fifth to ninth joints. End 
joint with five or six bristles; two long with natatory hairs, three or 
four short without hairs. Endopodite: two jointed; first jot with 
long bristle wreathed by long hairs and five short, bare bristles; 
second joint bears long bristle with two wreaths of long hairs, minute 
spine at distal end of joint. 
Mandible (figs. 3F, H, 1): Coxale endite bifurcate, with rows of slender 
spines. Basale: ventral margin with seven bristles; two long, distal 
bristles with wreaths of long hairs; five short, proximal bristles with 
short hairs. Dorsal margin with three bristles: two at distal corner; 
