ORDER II CRINOIDEA—CAMERATA 137 
Cupressocrinus, Goldf. (Fig. 238). Tegmen very small; the greater part of 
the ventral surface covered by the so-called consolidating apparatus. This is 
composed of five petaloid, horizontally truncated interradial pieces, which are 
laterally in contact, and enclose a large, central open space. The opening was 
probably covered by orals, as in Symbathocrinus ; while the consolidating plates 
served for the attachment of muscles. Five round apertures, through which the 
ambulacra entered the calyx, perforate the divisions between the consolidating 
plates ; one of the latter is pierced by the anal opening (Fig. 238, ¢). Arms 
provided with a wide and deep ventral furrow, lined on both sides w ‘ith jointed, 
closely abutting appendages ; of these there are several to each arm-plate, thus 
showing that they are different from true pinnules. Middle Devonian ; Eifel, 
Harz, Nassau, and Westphalia. (. crassus, elongatus, abbreviatus, Goldf. 
Myrtillocrinus, Sandb. Calyx deep ; tegmen formed by five lar ge symmetri- 
cal orals resting directly upon the radials. IB fused into a single plate, and 
pierced by the quadripartite canal of the stem. Devonian. 
Family 6. Stephanocrinidae. Wachsmuth and Springer. 
Calyx cup-shaped, composed of three elongate basals, five radials, and fwe inter- 
radials. Radials deeply forked ; the prongs formed by the margins of two contiguous 
radials extending upward between the arms, and building together with the interradials 
a row of pyramids. Radial incisions goed by the ambulacral grooves, which are 
roofed over by two rows of covering pieces ; those of 
the same row closely anchylosed. First costals semi- 
lunate, and resting within a horseshoe-like concavity 
near the outer end of radial incisions. Tegmen 
constituted of five large triangular orals. Arms 
very short, composed of about ten jreces, all of which 
are axillary, and give off side arms. The latter are 
biserial, non-pinnulate, and are made up of long, 
strongly cuneiform joints. Ordovician and Silurian. 

Fic. 239. 
Stephanocrinus, Conrad (Lhombifera, Barr.), _ Stephanoerinus anqulatus, Conrad. Sil- 
urian ; Lockport, New York. , Side view 
(Fig. 239). This unique genus is distinguished of calyx, natural size; 6, Summit aspeet, 
from all other Larviformia by the biserial and enlarged ; projecting Upper ends nae 
branching character of the arms, as well as by 
the presence of small interradials. Anal aperture situated near the summit of 
one of the interradial projections. Ordovician (Etage D); Bohemia. Silurian ; 
North America. 
Order 2. CAMERATA. Wachsmuth and Springer. 
(Sphaeroidocrinacea, Neumayr.) 
The lower arm-plates incorporated into the dorsal cup by means of supplementary 
plates. All plates of the calyx united by close sutures, and immovable. Tegmen in 
the form of a solid vault, composed of rigidly united plates. Mouth- and food-grooves 
completely covered ; the covering pieces of the latter frequently incorporated in the 
tegmen. Anal opening eccentric or subcentral, frequently situated at the end of a 
proboscis-like anal tube. Interradials constantly present in all interrays ; nde 
