‘ 
238 S. Lyon and S. A. Casseday on new species of Crinoidea. 
Dimensions of medium sized Adult : 
Breadth of basal pieces, - . - . - “45 inch. 
Height of subradials, - : - - - ei 
idth o ve - - - - - - 45 
Length of first 4 radials, - - - - et} oe 
Length of arms, - . - - - i ee 
This crinoid is referred with some doubt to Forbesiocrinus of de Ko- 
ninck as defined by Jas. Hall, Geol. of Iowa, part 2, p. 630. In technical 
strictness this is not Forbesiocrinus, and will not fall into that genus, 
advanced, and the number of genera erected, to receive analogous forms 
as not diminished the difficulties pertaining to the subject. : 
Our species has from four to six anal pieces and no more, the generic 
e differences should certainly be generic, yet the analogy of form is 
such that it is proposed to modify and extend the generic formula and 
admit this and other allied forms. 
Geological position and locality. Subcarboniferous limestone, Hardin 
Co., Ky., and in similar rocks in Indiana. 
Actinocrinus. (Miller.) 
Actinocrinus cornigerus, sp. nobis. 
Body. General form subglobular, conical, below the arms having the 
form of an inverted cone which is about two-thirds the length of the en- 
tire body, the whole surface beautifully ornamented with carina, spines 
| 
Basal pieces, three, prominent, nearly equal in size, forming together a 
large irregular hexagon; each piece has a broad leaf-like expansion raised 
pieces. The lateral markings surrounding the base are quite prominent 
and form around it a raised hexagon, ; 
Second radials, five, hexagonal, a little smaller than the first radials 
and similarly ornamented. . 
Third radials, five, two of which are hexagonal, the others being 464 
g strong rib which proceeding from the centre of the 
and extending over the second radials, bifurcates near the centre of the 
third, giving off two ribs. From the upper margin of the third 
