Fig. 3. The "Nave Encrinite" (_Actinocrinus triacontadactylus_, or thirty-fingered, of Miller), from the mountain limestone. This is a good example of the structure of the receptacle in this group of Crinoideans, which is distinguished by the arms passing off at right angles from the periphery of the receptacle, like the spokes of a wheel; whence the name, Nave Encrinite. The upper part is covered by closely adapted plates, and the buccal aperture or mouth is situated at the side. The stem of this group is thickly beset with side-arms. (Fig. 7 is a very small detached one.) The arms are numerous (amounting to thirty in the species figured), and of great length; these subdivide into jointed filaments of extreme minuteness. Slabs of limestone are often entirely covered with them, and many layers are wholly made up of their aggregated remains. The plates of the receptacle are generally highly ornamented: in one species the sculpturing so closely resembles that of the _Marsupites ornatus_ of the chalk, that it was with difficulty I convinced Mr. Parkinson that the latter did not possess a stem, and therefore was not an Actinocrinite.[46] [Footnote 46: See Medals of Creation, p. 325; Wonders of Geology, p. 664; Miller's Crinoidea, p. 94.] Figs. 4, & 5. Portions of receptacles of Actinocrinites. Figs. 6, & 8. Fragments of stems of a Pentacrinite (_Pentacrinus scalaris_, of Goldfuss); from Gloucestershire. Fig. 9. A Pentacrinite expanded on a slab of Lias-shale. Gloucestershire. Fig. 10. Stem, receptacle, and arms of a Crinoidean (probably a _Cyathocrinite_); it is drawn in an inverted position. The figure is stated by Mr. Parkinson to be copied "from a plate by Dr. Capeller." Neither the locality, nor the stratum from which it was obtained, is mentioned. Fig. 11. Part of the stem of a Pentacrinite (_P. basaltiformis_, of Miller); from the Lias. Gloucestershire. Fig. 12. The receptacle of a Crinoidean (_Platycrinus lævis_, of Miller); from the mountain limestone, Ireland. Fig. 13, ossicles of the arms; and fig. 14, joints of the stems, slightly magnified. Fig. 15. "The superior part of the Briaræan pentacrinite."--_Mr. Parkinson._ (_Pentacrinus Briareus_, of Miller.) The specimen is a slab of Lias, almost wholly made up of crinoideal remains. In relief on the surface are the stems and dislocated ossicles of the receptacle; the latter are thus enumerated by Mr. Parkinson;--_a_, scapula; _b_, clavicle; _c_, first bone of the arm; _d_, second arm-bone; _e_, commencement of the two series of bones forming the fingers.