BATOCRINID^. 445 



Remarhs. — We regard Batocrinus hulhosus R. and H. as identical with this 

 species, although the type specimens show slight variations. The disk of 

 " B. biilbosus " is somewhat more depressed, due perhaps to outside pressure, 

 and the plates of the disk are less convex ; but variations of this kind are 

 known to occur within the limits of almost every species. The two speci- 

 mens agree essentially in the arrangement of their plates, in the mode of 

 branching of the arms, they have the same nuinber of interbrachials, and 

 these connect in both forms with the plates of the disk. 



( ?) Lobocrinus Hageri (McChesnet.) 

 Plate XXX. Figs. 9, 10. 



I860. Actinocrinus Hageri — McChesnet; New Palaeoz. Foss., p. 28. 



1867. Actinocrims Hageri — McChesnet; Chicago Acad. Nat. gci., p. 21, Plate 4, Tig. 1. 



1873. Batocrinus Hageri — Meek and Woethen ; Geo). Rep. Illinois, Vol. V., p. 367. 



18S1. Batocrinus Hageri — W. and Sp. ; RcTision Palseocr., Part II., p. 166. 



Approaching Dizygocrinus rotundus, but the dorsal cup more conical and 

 proportionally higher ; slightly depressed between the rays ; the anal tube 

 smaller and more excentric. Plates flat, without ornamentation, and the 

 suture lines indistinct. 



Basals forming a low saucer-shaped, hexagonal disk, rounded at the bot- 

 tom, and excavated for the columnar attachment, which is small. Eadials 

 half as wide again as long. First costals quadrangular, three times as wide 

 as long, the second wider than the first. Distichals in two rows, those of the 

 upper row wider and axillary ; followed by 2 X 2 palmars, which support the 

 free arms. Arm openings directed obliquely upwards, arranged in groups of 

 four, with a slight indentation between the rays, of which that at the pos- 

 terior side is considerably the deeper. Arm structure unknown. Inter- 

 brachials : '1, 2, 2, 2, the upper row in contact with the plates of the 

 ventral disk; the first plate smaller than usual in this genus, and fre- 

 quently not reaching to the full height of the second costals. Anal plate 

 a little smaller than the radials ; succeeded by 3, 3, 2, and 2 plates. Ven- 

 tral disk slightly grooved at the posterior side, depressed convex, the plates 

 nearly flat and almost equal in size. Anal tube excentric, very narrow and 

 short. 



Horizon and Locality. — Upper Burlington limestone, Burlington, Iowa. 



Type in the (Worthen) Illinois State collection. 



Remarks. — "We have placed this species somewhat reluctantly under 



