50 



the artist mistook a slight displacement filled with stone for a 

 plate, and there should have been only two brachials in the figure. 

 There are, therefore, ten arms in this species, two from each ray. 

 They are composed of long, rounded cuneiform plates that bear 

 numerous armlets. In the lower part of the arms every third 

 plate bears an armlet, but higher up every second or alternate 

 plate bears an armlet. The armlets are composed of short plates 

 and look like small arms. 



First azygous plate is quadrangular, broadly truncated, a sub- 

 radial separates two first radials and rapidly expands to the sum- 

 mit of the calyx. The other azygous plates, vault aud proboscis 

 are not preserved in our specimen. 



This species is readily distinguished from B. forrnosus by the 

 surface ornamentation aud absence of pits at the angles of the 

 plates, as well as by comparison of the specific details. It is 

 still farther removed from Banjcrinus blairi and Barycrinus 

 bocmvillensis, and need not be compared with any other described 

 species, as there is none for which it might be mistaken. 



Found in the Keokuk Group in Washington County, Indiana, 

 and now in the collection of Wm. F. E. Gurley. 



Family DOLATOCRINID.E. 



DOLATOCRINUS COBPOEOSUS, D. sp. 



Plaie V, Fig. 1, basal view: Fig. 2, snmmif vieu; ihe sutures 



between the plates being too obscure to illustrate; Fig. 3, 



azygous side of the same specimen. 



Species large. Calyx subhemispheroidal, broadly truncated, at the 

 base, and constricted below the arm bases. Eadial ridges mere 

 rounded elevations across the plates which are interrupted by cen- 

 tral nodes. Surface ornamented with numerous radiating ridges 

 that do not coalesce in the centers of the plates. Column large, 

 round and having a remarkably large, cinque-foil canal. 



Basal plates hidden by the column and a rounded rim that sur- 

 rounds it, on the basals and at the commencement of the first 

 primary radials. First primary radials wider than long and of 

 unequal size, two of them, on the azygous side, being larger than 

 the others, as shown in the upper part of figure 1. Second primary 

 radials large, about one-half wider than long, quadrangular, sides 



