314 Neio Species of Crinoidea from the 



branches ; the first bifurcation on the eighth to the twelfth 

 plate, the second from the tenth to the fourteenth of the 

 outer branch ; the inner branch usually simple. 



First anal plate proportionally large, pentangular, resting 

 between the sub-radials, and supporting one side of a first 

 radial and the two anal plates. Second anal plate smaller 

 than the first, slightly elongate, hexagonal ; the succeeding 

 plates regularly hexagonal, very gradually decreasing in size 

 upwards, and forming by their union with others a short, 

 strong proboscis. 



Arms composed of very short plates, alternately longer 

 and shorter on opposite sides, the longer side supporting 

 the tentacula, which are long, very strong, and composed 

 of cylindrical joints. Surface of plates smooth, with a 

 series of small, deep pits at the angles of the plates. 



This species may be readily distinguished from any 

 other of the genus by the low, broad cup, the number and 

 bifurcations of arms in the antero and postero-lateral rays, 

 the simple arm of the anterior ray, and the peculiar pits at 

 the angles of the plates of the body. 



Geological formation and locality. In rocks of the age 

 of the Keokuk limestone, Crawfordsville, Indiana. Collec- 

 tion of Wabash Col/cg-c. 



Scaphiocrinus nodobrachiatus (n. s.). This sj^ecies re- 

 sembles the preceding in the general aspect of the arms, 

 but they are more evenly cylindrical, the margins of the 

 plates not thickened, or but slightly so, and each plate 

 marked by a single rounded node, instead of two sharp or 

 spiniform nodes to each plate as in S. spi nob rack iatus. The 

 arms are extremely elongated. 



The characters indicated above seem sufficient to dis- 

 tinguish the species. 



Geolog'ical formation and locality. In rocks of the age 

 of the Keokuk limestone, Crawfordsville, Ind. Collection 

 of Wabash Colleg'e. 



