MELOCRINID&. 285 
3X10, each series supporting two arms, or twenty from the calyx. The 
two inner arms branch three times, the outer ones remain simple. Above 
the last bifurcation, according to Hall, the arms are composed of a “ double 
series of wedge-formed plates, and below these points of a simple series of 
quadrangular plates,” with rounded pinnules. 
Horizon and Locality. — Same as last. 
Mariacrinus aureatus 8. A. Mitier. 
(After Miller.) 
1891. Adv. Sheets 17th Rep. Geol. Surv. of Indiana, p. 34, Plate 6, Fig. 36. 
Calyx very small. Dorsal cup bowl-shaped ; plates covered with angular 
ridges passing out from their centres. Basals four, unequal; exposed 
beyond the column. Radials the largest plates of the calyx, wider than 
high. First costals a little smaller, their width greater than the length ; 
pentangular or hexangular. Second costals as long as wide. Distichals two 
in the three anterior rays, three in the posterior ones; the second plate of 
the former axillary. Interradial areas elongate, subovate. Regular sides 
composed of seven or eight plates: 1, 2, 2, 2; the first nearly as large 
as the radials. Interdistichals one or two. The anal side has nine or ten 
plates, there being three in the second, and four in the third row; the plates 
of the upper row very small. Arm structure and tegmen not preserved in 
the specimens. 
Fforizon and Locality. — Niagara group ; St. Paul, Ind, 
MACROSTYLOCRINUS Hatt. 
1852. Hatz; Paleont. N. York, Vol. II., p. 203. 
1857. Picrer; Traité de Paléontologie, Vol. IV., p- 329. 
1862. Dusarpry and Huré; Hist. natur. des Zooph. Echin., p. 149. 
1863. Hatt; Trans. Alb. Inst., Vol. IV., p. 207 (Abstr. p. 12). 
1879. Hat; Mus. edit. 28th Rep. N. Y. State Mus. Nat. Hist., p. 128. 
1879. Z:rre.; Handb. d. Paleont., Vol. I., p. 368. 
1881. W. and Sp.; Revision Paleocr., Part II., p. 102; also Proceed. Acad. Nat. Sci. Phila., p. 276. 
1881. Hatt; 11th Ann. Rep. Geol. of Ohio, p. 256. 
1882. RixeveserG; Journ. Cincin. Soc. Nat. Hist., Vol. V., p. 119. 
1882. Ds Loriot; Paléont. Francaise, Tome XI., Crinoides, p. 56. 
1883. W. and Sp.; Revision Paleoer., Part III., p. 102; also Proceed. Acad. Nat. Sci. Phila.,p. 324. 
Syn. Actinocrinus (in part)— Lyon; Proceed. Acad. Nat. Sci. Phila., 1861, p. 411. 
= Syn. Cyathocrinus (in part) —Hati; Doe. edit., 28th Vol., N. Y. State Mus. Nat. Hist. (Explana- 
tion of Plate 13). : 
Syn. Clenocrinus (in part) — Suumanp; Trans. Acad. Sci. St. Louis, Vol. IL., p. 360. 
