A treatise on zoology . a few iAmb. lax fused to IBr,in adult, and supports stout, incurved, unbranching rami ; no stem ;attachment by base of patina. No sacculi. The arm-structure led Jaekel(1891) to combine these forms with the Eugeniacrinidae. Genera—Holopus, dOrb. (1837), Tertiary of Italy, Recent, Caribbean Sea, shallow 198 THE CRINOIDEA Avater (Figs. CXXI. and XXXIV.). Cyathidium, Steenstrup (1846 ; syn. , Michelin), Uppermost Cretaceous to Miocene, Denmark and Italy. Family 9. (?) with patina of 5 RK, enclosingfunnel-shaped cavity open below, restin
A treatise on zoology . a few iAmb. lax fused to IBr,in adult, and supports stout, incurved, unbranching rami ; no stem ;attachment by base of patina. No sacculi. The arm-structure led Jaekel(1891) to combine these forms with the Eugeniacrinidae. Genera—Holopus, dOrb. (1837), Tertiary of Italy, Recent, Caribbean Sea, shallow 198 THE CRINOIDEA Avater (Figs. CXXI. and XXXIV.). Cyathidium, Steenstrup (1846 ; syn. , Michelin), Uppermost Cretaceous to Miocene, Denmark and Italy. Family 9. (?) with patina of 5 RK, enclosingfunnel-shaped cavity open below, restingon a solid mass which may representfused BB or a proximale. lax articulatedto IBrp and supporting 2 stout ramiwhich abut on adjoining rami. Axialcords lie close to inner walls of —EudesicrinuSj de Loriol (1882) ;and Cotylederma, Quenst. (1852 ; , E. Deslongch.), both would place these genera nearthe Plicatocrinidae ; they are usuallyreferred to Eugeniacrinidae or Order 3. Dicyclica Camerata (= Camerata, W. & Sp. 2)Cfy^)- Fig. CXXI. Adult Holopis Rung!, from anterior.(From A. Agassiz, after P. H. Carpenter.)Enlarged by one-twelfth, . i.,,,tt^ Dicyclica m which all IBr and usually 11 Br are incorporated in the dorsal cup by iBr, at first loosely, but afterwards by close suture. IBB always the primitive 5. A plate always between r. and 1. post. RR, resting on post. B, and followed by others leading up to the anus. Mouth and ambulacra subtegminal. Arms pinnulate. Family 1. Reteocrinidae. Dicyclica Camerata with RR and Br sepa-rated by supplementary plates irregular in size, shape, and arrangement, andforming depressed interradial areas, the posterior of which is divided by asingle vertical series of prominent plates leading from to the eccentricanus. Genus—Reteocrinus, Billings (1859 ; see W. &, Sp., 1897), Ordo-viciaii, N. America (Fig. CXXII.); 2-3 IBr ; about 6 IIBr, of whicli thepinnules, borne from IIBrg onward
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