MELOCRINIDZ&. 303 
as wide. Distichals two, the two divisions separated by one or two inter- 
distichals. Palmars apparently not united laterally, and there may have 
been two appendages to each ray. Interradial spaces depressed in the upper 
portions; arranged: 1, 2, 3, with numerous plates above, which connect 
with others in the disk. Anal area somewhat the widest, and with three 
plates in the second row. Ventral disk almost flat; composed of very uni- 
form, slightly convex pieces. Anus excentric, probably without a tube. 
Horizon and Locality. — Niagara group; Waldron and Hartsville, Ind. 
Type in the American Museum of Natural History, New York. 
Melocrinus parvus W. and Sp. 
Plate XXIT, Fig. 8. 
1892. W. and Spe.; Amer. Geologist (September number), Vol. X., p. 144. 
A small and very slender species of the type of Melocrinus Roemeri, hav- 
ing like that species five uniserial radial appendages. Dorsal cup obpyr- 
amidal, the interradial spaces deeply depressed, and the cross-section at the 
top of the costals distinctly pentalobate. The plates a little convex and 
covered with obscure ridges. 
Basal cup almost cylindrical, its upper end slightly the widest, the lower 
face completely covered by the column; the plates as high as the radials, 
and the interbasal and basi-radial sutures distinctly grooved. Radials a little 
longer than wide. First costals of the same proportions as the radials. 
Second costals smaller, proportionally shorter, and irregularly axillary ; one 
of their upper faces short and giving off an arm, the other a row of distichals, 
which are followed by higher orders of brachials, and arms given off at inter- 
vals from opposite sides. Interbrachials three at the regular sides, and four 
at the anal side, the latter having three plates in the second row against two 
at the other sides. Ventral disk convex, the interambulacral spaces a little 
depressed ; composed of moderately large, slightly convex plates. Arms 
excentric. 
Horizon and Locality. — Niagara group; St. Paul, Ind. 
Type in the collection of Wachsmuth and Springer. 
Remarks. — This species differs from M. Roemeri in the narrower and 
less spreading base, in the proportions of the radials and costals, and in the 
convexity of the plates. 
