352 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
symmetry of the Crinoids generally. Another most remarkable feature, 
which separates this family distinctly from all other Camerata, is the com- 
partments enclosing the arms, which are formed by processes or partitions 
attached to the outer sides of the disk, and are supported by the inter- 
brachials and interdistichals. 
The family was restricted to the Upper Silurian, with the exception of 
a single species found in the lower Devonian of the Eifel. It was the lead- 
ing family of its epoch in the number of species discovered, there being 
twenty-one from America, and eighteen from England and Sweden, but only 
two genera. 
EUCALYPTOCRINUS Gotpr. 
1826. Go.pruss; Petref. German., Vol. I., p. 214, and 1838, Nova Acta Leop. Vol. XIX., 1, p. 335. 
1841. Miter; Berl. Akad. d. Wissensch., p. 210. 
1841. Hatt; Paleont. N. York, Vol. IL., p. 207. 
1843. Roemer; Rhein. Uebergangsgeb., p. 62, and 1855, Lethaea Geogn. (Ausg. 3), p. 257, and 1860, 
Silur. Fauna West. Tenn., p. 48. 
1853. De Koytyck and Lenon; Recher. sur les Crinoides du Terr. Carbonifére de la Belgique, p. 74, with 
diagram. 
1857. Prcrer; Traité de Paléontologie, Vol. IV., p. 307. 
1862. Dusarprn and Hupr; Hist. Nat. des Zooph. Echin., p. 115. 
1863. Hatt; Trans. Albany Inst., Vol. IV., p. 197. 
1866. Scuurtze; Monogr. Echin. Eifl. Kalk., p. 90. 
1878. AnGELIN; Iconogr. Crin. Suec., p. 16. 
1879. Tatu; 28th Rep. New York State Mus. Nat. Hist., (Ed. IT.), p. 141. 
1879. Zirrer; Handb. der Palwontologie, Vol. L., p. 379. 
1885. Quvenstept; Handb. d. Petrefactenkunde (Ausg. 3), p. 963. 
1885. W. and Sp.; Revision Paleoer., Part IIL, p. 127 (Proceed. Acad. Nat. Sci. Phila., p. 349). 
1889. S. A. Mrtrer; N. Amer. Geol. and Paleont., p. 243. 
Syn. Hypanthocrinus Puitires, 1839; Murchison’s Silur. System, p. 672, Plate 17, Fig. 3; Zittel, 
1879; Angelin, 1878; S. A. Miller, 1880. 
Calyx with the arms attached more or less ovate; without the arms 
resembling a wine bottle with concave bottom and slender neck; the neck 
surrounded by ten longitudinal partitions closed from above, and forming 
ten niches or compartments into which the arms, in pairs, and to their full 
length, exactly fit. Dorsal cup composed of four basals, five radials, 2 x 5 
costals, 2 X 10 distichals, 1 * 20 palmars, 3 X 5 interbrachials, and 1 X 5 inter- 
distichals. The basals, which form an inverted funnel-shaped cup, are not 
visible from a side view, and the talyx rests upon the edges of the inflected 
lower portions of the radials; the plates varying in size, the anterior one 
larger than the rest. Axial canal five-rayed, the anterior basal pierced by 
two of its rays. First costals quadrangular, the second pentangular unless 
the upper angle is truncated by the interdistichal. First distichals larger 
