BATOCRINIDZ. 439 
them the interbrachials are continuous with the interambulacral plates. 
Again Batocrmus has well defined, large respiratory pores, which are ap- 
parently unrepresented in Lobdocrinus. 
Lobocrinus Nashville (TRoosT). 
Plate XXXI. Fig. 1. 
1849. <Actinocrinus Nashville —'Troost; Catal. of Crinoidea (Proceed. Amer. Assoc. for Adv. Sci., 1849, 
p. 60). 
1858. <Actinocrinus Nashville — Hall; Geol. Rep. Iowa, Vol. I., Part 1I., p. 609, Plate 15, Fig. 4, and 
Plate 16, Figs. 4a, b. 
1873. Batocrinus Nashville — M. and W.; Geol. Rep. Illinois, Vol. V., p. 368. 
1881. Batocrinus Nashville — W. and Se.; Revision Paleocr., Part IL, p. 167 (Proceed. Acad. Nat. Sci. 
Phila., p. 341). 
1885. Actinocrinus Nashville — QuunsteDt ; Handb. der Petrefactenkunde, Plate 77, Fig. 2. 
1890. Batocrinus Nashville — WortuHEN; Geol. Rep. Illinois, Vol. VIII., p. 85, Plate 13, Fig. 5. 
Calyx higher than wide, urn-shaped, truncated at the base, the lower 
edge somewhat projecting laterally and rounded off. Dorsal cup higher 
than the ventral disk, distinctly lobed at the arm regions, contracted at the 
basi-radial suture, whence it spreads at first gradually, and then rapidly, to 
the arm bases, which form a projecting rim around the calyx. Plates moder- 
ately convex, without ornamentation ; the suture lines distinct. 
Basals large, forming a subcylindrical cup almost twice as wide as high ; 
the interbasal sutures slightly indented. Radials large, generally wider than 
long, their median portions raised into a transverse tubercle. Costals one 
third the size of the radials, a little wider than long; the first quadrangular, 
the second pentangular. Distichals 2X 10; followed by 1X 20 palmars, 
which project upward and outward, and support the arms. Arm facets 
directed upwards. Arms twenty; arranged in pairs, with deep depressions 
between the rays, and smaller ones between their main divisions. Inter- 
brachials: 1, 2, 2, 2, the last two resting between the arm bases. Anal plate, 
as a rule, a little higher than the radials; succeeded by three rows of three 
plates each. JInterdistichals one, resting between the second distichals. 
Orals and radial dome plates — the latter of a first and second order — 
more or less highly convex, contrasting considerably with the small supple- 
mentary pieces surrounding them, which are quite numerous near the arm 
bases. Anal tube strong, almost central; composed of large tumid plates, 
which gradually decrease in size upwards. At a height of an inch and a half 
from the base, the tube has a ring of five spiniferous plates, the spines some- 
times nearly an inch long, and directed horizontally. Column stout, and, so 
