——_ 
r= a 
ipa ar 
— 
— — . SS 
Fe fo . 
499, THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
grow more convex upward. Interbrachials two; the first almost as large as 
the radials; the second much smaller and arched over by the two upper 
brachials. Anal plate considerably longer than the radials; followed by 8, 
Z, and | plate; the latter generally in contact with the interambulacral 
pieces. Ventral disk a little shorter than the dorsal cup, hemispherical, 
surmounted by a short slender anal tube; the plates convex. Column stout, 
the older joints rounded at their edges and projecting. 
Horizon and Locality. — Upper part of the Keokuk group at Bono and 
Canton, Ind.; also in the Lower part of the Warsaw limestone at Boon- 
ville, Mo. | 
Types in the collection of Wachsmuth and Springer. 
Dizygocrinus Gurleyi (S. A. Miter). 
Plate XXXIV. Fig. 19. 
1891. Batocrinus Gurleyi —Mruter; Adv. Sheets Geol. Surv. Ind. (17th Rep.), p. 66, Plate 11, Figs. 
9 and 10. 
(Not Batocrinus Gurleyi Rowuny and Harz, Aug. 1891). 
Of the type of Dizygocrinus originarius W. and Sp., and so closely resem- 
bling it that there is much doubt if it is a good species. The specimens from 
Bono, described by us as “ Hretmocrinus”’ originarius, only differ from the 
Boonville ones, which Miller has referred to Batocrinus Gurleyi, in having at 
the regular sides three interbrachials in place of two, and six pieces in place 
of five above the anal plate. The arms are a little longer and more slender 
at their tips, the angular ridges along the rays somewhat higher, and the 
surface markings upon the plates a little more distinct. The sides of the 
dorsal cup in one of Miller’s types are concave, in the other convex; while 
they are nearly straight in the Bono specimens. We give a figure of one of 
Miller’s types for comparison. 
Hlorizon and Locality. — Lower part of Warsaw limestone, Boonville, Mo. 
Type in the collection of I’. A. Sampson, Esq. 
Dizygocrinus originarius, var. adultus (W. and Sp.). 
Plate XX XV. Figs. 14 and 15. 
1881. Hretmocrinus adultus —W. and Sr.; Revision Palxocr., Part II., p. 175. 
Syn. Batocrinus mediocris—S. A. Mittmr; Adv. Sheets 17th Rep. Geol. Surv. Ind., p. 62, Plate 
10, Fig. 9. 
Syn. Batocrinus boonvillensis 8. A. MittnR; ibid., p. 65, Plate 10, Fig. 13. 
i 
