14 
SMITHSONIAN INSTITUTION 
To the foregoing American species may be added Rhodocrinus halli Lyon, from the 
Louisville limestone, a doubtful species from the Waldron, three species from the Racine 
dolomite, five from the Rochester shale, and one from the Helderbergian — all as listed in 
Bassler’s bibliography. 
The following five species of Angelin from Gotland, Encrinus interradialis, ornatus, 
laevis, qiiinqangidaris and speciosiis, with 4 arms to the ray, are referred tO’ this genus, and 
probably two or more of them are synonyms. 
Eudimerocrinus multibrachiatus new genus and species 
Plate I, figs, ig, iga, h, 14 
The difference in arm structure between this and all species referred to 
Dimerocrinus is so great that to be consistent with the practice followed in other 
cases, it seems imperative to propose a new genus for its reception. While in 
those forms the arms are always simple, not branching beyond the calyx, here 
they undergo several bifurcations at wide angles up to as many as three, giving 
6 or 8 final branches. These are all stout, and biserial both above and below the 
bifurcations — a type of arm highly distinctive of several genera, such as 
Abacocrimis, Clonocrinus, Megistocrinus, etc. In the composition of the calyx 
there is no difference, and with specimens consisting of the calyx alone it would 
be impossible to point out any character for distinction more than specific. But 
we have two unusually fine specimens, with the arms almost completely pre- 
served to the numerous bifurcations, and both entirely freed from the matrix, 
so that the characters of the calyx are fully disclosed on all sides. The surface 
structure is remarkably clear and distinct, with strong sculpturing, many of the 
plates sharply projecting and almost spinose. 
If in this species the interbrachials extended down to a connection with the basals, it 
might fairly go with Eiicrimis veniistus and E. minor of Angelin, for which Wachsmuth and 
Springer established the genus Anthemocrinus'^ under the Rhodocrinidae. 
Horizon and locality. Beech River formation, Brownsport group, Niagaran ; Decatur 
County, Tennessee. 
CYPHOCRINUS S. A. Miller 
Plate I 
Cyphocrinus Miller, i8th Ann. Rep. Dep. Geol. Indiana, 1894, p. 304 (adv. sheets 1892). — Bather, Treatise 
on Zool., 3, 1900, p. 199. — Weller, Bull. Chicago Acad. Sci., 4, pt. i, p. 75 (synonymy discussed). — 
Zittel-Eastman, Textb. Pal., 2d Ed., 1913, p. 187. — Bassler, Bibliogr. Index, 1915, p. 340. 
Hyptiocrinus Wachsmuth and Springer, Am. Geol., 10, 1892, p. 138; N. A. Grin. Cam., 1897, p. 200. 
Calyx constructed as in Dimerocrinus, but low, wide, and recurving from 
a narrow obconical base to a spreading, inverted bowl, with arms directed down- 
wards; axillary and central tegmen plates spiniferous. 
Genotype. Cyphocrinus gorbyi S. A. Miller. 
Distribution. Silurian ; not known outside of America. 
1 Rev. Pal., 2, 1881, p. 208. See also Jaekel, Phylogenie und System, 1918, p. 40, where he claims that 
E. minor may have only 4 iBB. 
