No. 1608.] NEW SPECIES OF CRINOL DS—CLARK. DG 
more or less normal multiradiate condition in 7ropiometra carinata. 
It may be that the 9-rayed condition arises from a departure from the 
usual pentamerous type which affects the entire animal, and not from 
a mere doubling of the rays. 
It is well to here call attention to the fact that Promachocrinus and 
Decametrocrinus are not nearly related as supposed by Carpenter and 
Minckert; the former belongs to the Antedonide and is near to 
Heliometra, while the latter belongs to the Eudiocrinide and 1s re- 
lated to Hudiocrinus. 
Family ANTEDONID 4. 
Genus TRICHOMETRA. 
TRICHOMETRA VEXATOR, new species. 
Centro-dorsal subconieal, about twice as broad as high, bearing 40 
to 60 cirri, closely crowded together and without definite arrange- 
ment; there is a moderately large bare polar area. 
Cirri about 20 mm. long with 40 to. 45 joints on the proximal part 
of the centro-dorsal, those near the apex being about half as long with 
25 to 30 joints; first cirrus joint short, second squarish, third and 
fourth about half again as long as broad, fifth and following to about 
the fifteenth about twice as long as broad after which they decrease 
gradually in length, the last 15 or 20 being squarish; the distal end 
of the elongate proximal joints project slightly on the dorsal side, 
and the dorsal side of the shorter distal joints 1s rather strongly 
convex, but true dorsal spines are not developed; the opposing spine 
is prominent and sharp, terminally situated, triangular, in length 
about equal to the diameter of the penultimate joint. 
Radials concealed; first costals short and broad, the lateral edges 
produced and in apposition, the anterior border strongly concave in 
the median line; costal axillaries about as broad as long, all the sides 
somewhat concave, with a rounded posterior border, incising the first 
costal. Ten arms 60 mm. to 65 mm. long; first brachials short, con- 
cave anteriorly, united interiorly in their posterior half; second 
brachials larger, triangular; third and fourth brachials (syzygial 
pair) about as long as wide, rather longer interiorly than exteriorly, 
the hypozygal being somewhat wedge-shaped; following six bra- 
chials oblong, broader than long, then becoming triangular about as 
long as broad, and elongate and somewhat swollen distally. Syzygia 
occur between the third and fourth brachials, again between the ninth 
and tenth, and distally at intervals of two bifascial articulations. 
The lower pinnules are badly broken in all the specimens; the first 
pinnule and the pinnule on the fourth (i. e., “ third”) brachial are 
exceedingly slender, greatly elongated, with all but a few of the basal 
joints extremely elongated; the following pinnules are much shorter, 
