42 
SMITHSONIAN INSTITUTION 
CARPOCRINUS Muller 
Plate 7 
Carpocrinns Miiller, Monatsb. Berlin Acad. Wiss., i, 1848, p. 208: Verb. Naturh. Verein, 12, 1855, p. 19. — 
Wachsmuth and Springer, Rev. Pal. 2, 1881, p. 105 (full synonymy, pp. 107, 108). — Bather, Treatise 
on Zool, 3, 1900, p. 166. — Zittel-Eastman, Textb. Pal, 2d ed., 1913, p. 194. — Jaekel, Phylogenie und 
System, 1918, p. 37. 
Phoenicocrunus Austin, Ann. Mag. Nat. Hist., ii, 1843, p. 205. — Abracrimis D’Orbigny, Prodr. Pal, i, 
1850, p. 47. — Habrocriims Angelin, Icon. Crin. Suecc., 1878, p. 3; Pionocrinus Ang., ibid., p. 4; Lepto- 
crinus Ang., ibid., p. 3. 
Calyx rotund with protuberant base; iBr usually in several ranges; anals 
in prominent ridge ; arms stout, not over two to the ray, with brachials uniserial, 
quadrangular or slightly cuneate, bearing a pinnule on each side, sometimes 
two at the longer face. 
Genotype. Actinocrinites simplex Phillip.s. 
Distribution. Silurian ; Gotland, England, America. 
This genus, treated under several names, is one of the most prolific of the north Euro- 
pean Silurian, from which no less than nineteen species have been described, all occurring 
in Gotland, and at least one also in England. A full list is given by Wachsmuth and Springer, 
Rev. Pah, 2, pp. 107-8. Representing as it does an early and simple Batocrinid type, some 
migrational extension into the American Silurian might well be expected, and in fact was 
looked for with confidence as the Niagaran fauna of Indiana and Tennessee began to show 
its remarkable development. So far this expectation has been realized by only a single species, 
which is believed to he fully characteristic as judged by the calyx alone. Eor comparison, and 
to illustrate the accompanying type of arms with their doubled pinnules, I am figuring on 
plate 7 a complete crown of C. simplex, the species which is common to England and Gotland. 
Carpocrinus sculptus new species 
Plate 7, figs. 2i-2ih 
Except for the absence of arms, the specimen is very perfect, the calyx 
being entirely free including the tegmen ; even of the arms there are short stumps 
in one ray, enough to show that they have the number, stoutness and uniserial 
brachials characteristic of the genus. The calyx is well rounded, with protuber- 
ant base, proportionally more elongate and with more ranges of iBr than usual. 
Median row of anal plates very conspicuous, passing up into the tegmen to an 
opening midway from the center and next to the posterior oral, bordered by a 
circlet of small convex plates. Tegmen strongly marked by 5 very distinct orals, 
4 small partly enclosing the much larger posterior one, and extremely conspicu- 
ous ambulacra with a double series of covering plates, passing outward and 
branching to the to arm-openings ; interambnlacra small and numerous. Surface 
of cup plates very ornately sculptured; this is sharp and distinct on the part 
which was imbedded in the soft matrix, fig. 21, but in fig. 2 \a. owing to erosion, 
the surface appears perfectly smooth. 
Two of Angelin’s species, Hahrocrinus ornatissimus and PI . ornatus, have a similar orna- 
mentation, but are otherwise different. 
IPorizon and locality. Laurel limestone, Niagaran; St. Paul, Indiana. 
