= —— 
498 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Remarks. — Professor Hall described this species as having but two plates 
above the anal piece, which is certainly abnormal, as our specimens clearly 
show the presence of three plates. 
Dizygocrinus montgomeryensis WorrHEy. 
Plate XX XIII. Figs. 3, and 4, and Plate XLVI. Fig. 10. 
1884. Batocrinus montgomeryensis — WortHEN ; Bull. 2, Illinois State Mus. Nat. Hist., p- 25, and Geol. 
Rep. Illinois, Vol. VIIL., p. 83, Plate 12, Figs. 2, 2a. 
Syn. Batocrinus Gurleyi — Rowiny and Haru (not 8. A. Miller),1891, Kansas City Scient., Vol. 
Wp: 15; Plate 35 Bic. 7. 
Syn. Batocrinus Sweetti — Row ey and Harz, 1891, ibid., p. 116, Plate 3, Fig. 8. 
Calyx of medium size. Dorsal cup saucer-shaped, lower than the ven- 
tral disk, rounded at the sides; the arm-bearing plates produced outward in 
form of tooth-like projections around the calyx. Plates from perfectly flat to 
slightly elevated, and without ornamentation. 
Basals small and short, forming a basin-shaped depression, which is com- 
pletely filled by the upper stem joint. Radials twice as wide as long, the 
upper face concave. First costals a little shorter and considerably narrower 
than the radials; the second slightly longer and somewhat wider. Distichals, 
as a rule, longer than the costals. They consist in the anterior ray of two 
series of four plates, which support the arms, the antero-lateral rays have 
2 x 2 distichals followed by three successive palmars in the calyx; while the 
two posterior rays in one division have four distichals and no palmars, in the 
other — that adjoining the anal interradius — two distichals and three pal- 
mars. The brachials of the two upper rows project outward, and are 
rounded and grooved laterally at the suture lines. Arm openings sixteen, 
the interspaces between the rays slightly widest ; the arm facet semi-circular, 
and directed obliquely upward. Arms in pairs, given off in the usual way ; 
they are long, very slender, tapering, and somewhat angular on the back ; 
the joimts of medium height, and their upper margins projecting over the 
lower ones of succeeding pieces. Pinnules long. Anal plate not quite as 
wide as the radials but higher, and followed by eight to nine interbrachials, 
against three or four at the other sides, those of the anal side being always, 
and those of the regular sides sometimes, connected with the plates of the 
disk. Ventral disk tumid, the centre of the plates covered with a very small 
tubercle, Anal tube slender, the plates smooth or slightly convex. Column 
