284 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
sloping upper faces of two radials. Neither is anything known of the con- 
struction of the disk. Column round, of moderate size, slightly tapering 
downwards; near the calyx the nodal joints are somewhat larger than the 
internodal ones, but at a length of about three inches all joints are of nearly 
equal size. 
Horizon and Locality. — Niagara shale ; Lockport, N. Y. 
Type in the collection of Dr. Eugene Ringueberg, Lockport. 
Mariacrinus plumosus* Hatt. 
Piate XXIII. Figs. 6 and 7. 
1859. Hatz; Palwont. New York, Vol. III., p. 110, Plate 3, Figs. 6-11. 
1881. W. and Sp.; Revision Paleocr. Part IL., p. 116. 
A small species. Dorsal cup apparently obconical; the surface orna- 
mented by strong radiating ridges, proceeding from the centre of the plates 
to adjoining ones. Basals about as long as wide. Radials a little longer 
than wide. Costals nearly as large as the radials and of similar form.  Dis- 
tichals 3 X 10, each row supporting two arms, twenty in all. Arms simple, 
rather long. composed of slightly cuneate joints. In the two outer arms, the 
second joint gives off a pinnule to the outer side, the third is a hypozygal 
joint, and the fourth gives off the second pinnule at the inner side; all suc- 
ceeding joints being pinnule-bearing. The two inner arms, according to 
Hall, support no pinnules up to the eighth joint, but this needs confirmation. 
Interbrachials, 1, 2, 2,2. The arrangement of plates in the anal interradius 
and construction of the ventral disk unknown. Column round, compara- 
tively large. 
Horizon and Locality. —1n the shaly layers of the Pentamerous limestone, 
Wheelock’s Hill, Litchfield, Herkimer Co., N. Y. 
(?) Mariacrinus ramosus* Hatz. 
1859. Hatt; Paleont. New York, Vol. III., p. 147, Plate 2, Fig. 6. 
1881. W. and Sr.; Revision Paleocr., Part IL, p. 116. 
Dorsal cup urn-shaped, the rays marked by strong ridges, which pass into 
the arms. Basals small. Radials and costals higher than wide. Distichals 
* We are somewhat in doubt as to the generic relations of this species, and think it possible from Hall’s 
fizure that it may possess infrabasals, and therefore belong to a different genus. We do not reproduce the 
original figure, because it does not agree with the description, either in the arrangement of the plates in the 
calyx, or the construction of the arms. We had no opportunity to see the type specimen, and only ean give 
an abstract of Hall’s description. 
