304 



COMPARATIVE ANATOMY 



CHAP. 



247). Hcterocrinus,Hcrpctocrinus, Calceocrinus, Catillocrinus, Pisocrinus, Hybocrinus, 

 locrinus, Symbathocrinus, Belemnocrinus, Gastrocoma (?), Cupressocrinus. 



B. Dicyclica. 



With dicyclic base (with infrabasals). Fam. Dendrocrinidse : Dendrocrinus, 

 Homocrinus, Poteriocrinus. Fam. Decadocrinidse : Botryocrinus, Barycrinus, 



m 



FIG. 248. Encrinus liliifonnis (original). 

 c l ca* Costals or primibrachials ; r, radials ; 

 co, stem ; p, pinnulae. 



FIG. 249. Cyathocrinus 

 longimanus (after Angelin). 

 pr, Ventral sac ; !, place where an 

 arm-branch has been removed ; 

 r, radials ; ba, basals ; ib, infra- 

 basals ; col, stem ; x, anal plates ; 

 co, costals or primibrachials. 



Atelestocrinus, Decadocrinus, Graphiocrinus, Encrinus (Fig. 248), (without anal 

 plates, ventral sac reduced to a short cone, Trias), Cromyocrinus, Agassizo- 

 crinus. Fam. Cyathocrinidse : Cyathocrinus (Fig. 249), Gissocrinus, Lecythocrinus. 

 Hypocrinus. 



The genus Marsupites from the Chalk, and the following extant families are 

 perhaps to be classed near the Inadunata ; in these latter five large separate orals 

 occur, the ventral sac being reduced to an anal tube, and no anals appearing in the 

 dorsal cup. Holopidaz (Fig. 250) (Lias, to present time), Hyocrinidce (Fig. 251) (Lias, 

 present time), Bathycrinidce (extant). 



