More than a year since I supplied Mr. Tyler (a grat 
174 W.S. Tyler on Spartaite of Breithaupt. 
of Encrinus in the private collection of Smithson, deposited at 
the Smithsonian Institution, shows five very minute pieces with 
“jn those generally considered the basal plates. If these minute 
poe were developed so as to assume the character of tne | 
asal plates, then those generally regarded as such would becom — 
subradials, as in our Crinoid. As this, however, seems never to — 
have beén the case in true Encrinus, it is reasonable to infer tha 
our Carboniferous form presents other differences entitling it) 
rank as the type of a distinct genus, The genus may be name | 
and characterized as follows: 
Erisocrinus, Meek & Worthen. Basal plates 5; subradials 
5; radials 2x5; anal and interradial pieces none, Column 
and arms unknown. We know the following species:— a 
1. E. typus M. & W.—Body, below the summit of the first 
radial pieces, basin-shaped, rounded below, and subpentagonal ; 
in outline above; composed of thick, smooth, scarcely conve’ 
plates; breadth 0°60 inch, height 0:24 inch. Basal pieces smal : 
about half hidden by the column; subradials three times 8 
large as the basal pieces, equally hexagonal ; first radial pieces | 
much larger, of equal size and form, being all wider than long, j 
ally deeper, in consequence of the larger size se ath, 06d; 
eight to top of first radials, 0°35 inch.—From the Coal-measies 
Bellevue, Nebraska. ~ 
Art. XXTI.—Analysis of a Carbonate of Lime and Mangn 
(Spartaite of Breithaupt,) from Sterling, Sussex wove ark 
ersey; by S. W. TyLer, A.B. Communicated, with rema™ 
y C. U. SHEparp, 
_ this College) with very fresh specimens of this mineral, OF 
analy during his residence at the Géttingen Laboratory’ is 
: pcs forwarded to me, under date of Nov. 10th, ae 
= has obtqined and be 
. Br. =2-815. Before the blowpipe, decrepitates ©. 
black without fusing. . With sale and microonemie 
toe. well- nown reaction of manganese. Not in Cl 
nee acid, but dissolves easily with effervescence 
