27 



difference in size and in surface ornamentation we do not ^regard 

 as of importance, especially where, as in this case, the two species 

 have the same general form and without careful examination 

 might be taken one for the other. A basal view of the two species 

 is alike. 



Found in the Hamilton Group, at Louisville, Ky., and now in 

 the collection of Wm. F. E. Gurley. 



DOLATOCKINUS LINEOLATUS, n. Sp. 



Plate III, Fig. 7, basal view; Fig. 8, side vieiv; Fig. 9, summit 

 view, the small plates near the arm openings 

 are not distinguished. 



Calyx hemispherical, very slightly constricted below the arm 

 bases, which protrude nearly horizontally. Surface ornamented 

 with fine radiating lines, in fascicles of three, that run from a 

 sharp prominent nod^, in the center of each principal plate, to 

 the central node in each adjacent plate. Radial ridges small, 

 sharp, continuous over the sutures and bearing a sharp node at 

 the center of each plate. Column round, rather small. 



Basal plates almost covered by the column. First primary radi- 

 als a little wider than long and not extending into the columnar 

 cavity. Second primary radials about twice as wide as long, quad- 

 rangular, sides nearly parallel. Third primary radials longer and 

 wider than the second; about twice as wide as long; expanding to 

 the lateral angles, pentagonal and bearing upon the upper sloping 

 sides the secondary radials. One of them bears upon each upper 

 sloping side three secondary radials and each of the other four 

 bear upon one upper sloping side three secondary radials and 

 upon the other one a single pentagonal secondary radial that bears 

 upon each upper sloping side two tertiary radials. There are, 

 therefore, three arms to each of four radial series and two arms 

 to the other one, making fourteen arms in all. The arm bases 

 project nearly horizontally. The arms are composed of a single 

 series of cuneiform plates. 



The first interradials are the larger plates of the body and have 

 nine sides. The second interradials are more than half as large 

 as the first and reach to the summit of the calyx. This plate in 

 the second range is followed by three plates, the central one is 

 the larger and unites with two plates on the vault and the lateral 



