198 ECHINODERMATA—PELMATOZOA SUB-KINGDOM III 
deep, generally with steep sides. Deltoids small, confined to the truncated 
upper face of the calyx. Lancet-plates in all but one species (P. caryophyl- 
latum) concealed bythe side-plates ; outer side-plates very small. Spiracles 
rarely present. Hydrospires pendent, and opening externally by a series of 
elongate slits with intervening ridges, distributed in sub-parallel order on the 
sloping sides of all the radial sinuses. ‘The slits are only partially covered 
by the ambulacral plates, and are sometimes visible for their entire length. 
Lower Devonian; Spain. Sub-Carboniferous ; Europe and North America. 
Cryptoschisma, E. and C. Calyx elongated, with a broad, flat, truncated 
upper face. Radial sinuses wide and open, their sloping sides pierced by 
hydrospire-slits, which are completely concealed by broad, petaloid ambulacra. 
Spiracles small, single, or more rarely double ; in the latter case the posterior 
pair are confluent with the anus. Represented by the solitary species C. 
Schultzi, d’Archiac et de Vern. Lower Devonian ; Spain. 
Orophocrinus, v. Seebach (Codonites, M. and W.) Calyx balloon-shaped to 
truncate ob-pyramidal, with more or less concave upper face. Section dis- 
tinctly pentagonal or stellate. Ambulacra narrow, linear to sub-petaloid. 
Deltoids generally visible in side-view, the posterior one wider than the 
others. Spiracles ten, varying from wide clefts along the sides of the ambu- 
lacra to narrow slits at their upper ends; the posterior pair separate from 
the anus. Hydrospire-slits almost completely concealed, being concentrated 
at the bottom of the radial sinuses. Stem round, composed of short, nearly 
equal joints. Pinnules extending to nearly twice the height of the calyx, of 
uniform thickness throughout, and composed of sharply cuneate pieces inter- 
locking from opposite sides ; ventral furrow wide, and covered by small pieces. 
Sub-Carboniferous ; Great Britain, Belgium, and North America. 
Order 2. IRREGULARES. Etheridge and Carpenter. 
Non-pedunculate Blastoids in which one ambulacrum and the 
corresponding radial are different in form and size from the 
others. 
Family 1. Astrocrinidae. T. and T. Austin. 

f This family embraces the three rare genera—Lleuthero- 
Fic. 325. crinus, Shum. and Yandell (Fig. 325), occurring in the 
Eleutherocrinus Casse- Tyeyonian of North America; <Astrocrinus, Austin; and 
dayi, Shum. and Yanda. 
Lower Devonian; Ky. Pentephyllum, Haughton. The two latter forms are found 
Ventral surface, 2, = : ; : 
(After E. and C.)’ ‘- in the Carboniferous Limestone of England and Scotland. 
1 [The substance of the editorial notes in brackets occurring throughout the Crinoid and Blastoid 
chapters has all been very kindly communicated by Mr. Charles Wachsmuth. Much of this matter 
embodies the results of original and as yet unpublished observations. Special acknowledgments are 
therefore due to Mr. Wachsmuth, without whose generous assistance the above-named chapters of 
the present edition would have been imperfect in many respects. —TRANS. ] 
