CRINOIDS. 173 



Calyx of medium size, with the dorsal cup usually some- 

 what shorter than the calycinal part above the arm bases ; very 

 broad below, the basals often extended into a prominent flange 

 or rim, with a concave base for the reception of the column. 

 Ventral spines like in D. inissouriensis, rather short, stout, but 

 sharply pointed at the ends. Arms short and slender. Sur- 

 face glabrate. 



Horizon and localities. — Lower Carboniferous, Upper Bur- 

 lington limestone : Ash Grove. 



Dorycrinus kelloggi Wokthen. 

 Dorycrinus kelloggi Wortben, 1875: Geol. Sur. Illinois, vol. VI, p. 513, pi. 

 xxix, figs. 8a-c. 



A small form, with obpyramidal calyx. Ventral side flat, 

 with nodose plates, the central one rather prominent. 



Horizon and localities. — Lower Carboniferous, Keokuk 

 limestone: Keokuk (Iowa). 



Dorycrinus intermedius Meek & Worthen. 

 Dorycrinus quinquelob us, var. intermedius Meek and Worthen, 1868: Proc. 



Acad. Nat. Sci., Phila., p. 346. 

 Dorycrinus quinquelobus, var. intermedius Meek & Worthen, 1875 : Geol. Sur. 



Illinois, vol. V, p. 3S5, pi. x, fig. 4, 



Closely resembles D. mississippiensis Eoemer, but some- 

 what smaller, with fewer arms and more slender ventral spines. 



Horizon and localities. — Lower Carboniferous, Upper Bur- 

 lington limestone: Quincy (Illinois); near Burlington (Iowa). 



Dorycrinus gouidi ( Hall). 



Plate xxlil, fig. 1. 

 Actinocrinus gouldi Hall, 1858: Geol. Sur. Iowa, vol. I, p, 613, pi. xv, 



figs. 6a-b. 

 Dorycrinus gouldi Meek & Worthen, 1873: G€ol. Sur. Illinois, vol. V, p. 



380. 



Calyx very large, massive, urceolate, strongly lobed ; trun- 

 cated below. Arms twenty in number. Ventral side hemi- 

 spherical, provided with six long, heavy spines which are often 

 covered with smaller spinous processes. Surface marked by 

 large, coarse nodosities. 



Horizon and localities. — Lower Carboniferous, Keokuk 

 limestone : Curryville, Kahoka (Clark county), Boonville, La 

 Grange; Keokuk ( Iowa). 



