I\ DR0D1 l 1'Im\ 



system, as a modern representative of Apiocrinus. A more careful exami- 

 nation has shown many points of difference, and I propose to establish a 

 new genus for this Crinoid, one of the most interesting brought to light 

 by any of the deep-sea dredging expeditions. 



It is most closely allied to a large group of Mesozoic Crinoids, and helps 

 us to understand more clearly many points in their morphology which 

 were left somewhat doubtful from our imperfecl knowledge of the Jurassic 

 Apiocrinidaa. In a preliminary notice of this Crinoid,* I proposed for it 

 the name of Calamocrinus Diomedae.f 



The first genus of the family (Encrinus) makes its appearance in the 

 Muschelkalk, and is specially characteristic of that formation. The Apio- 

 crinidae first appear in the inferior Oolite (Millericrinus). In the upper 

 beds of the Great Oolite we find Eugeniacrinus and Apiocrinus, the latter 

 extending to the Coral Rag. 



In the Oxford Clay and Coral Rag, Guettardicrinus and Millericrinus 

 abound, together with Apiocrinus. In these beds Millericrinus attains its 

 maximum development, but it also disappears entirely, as well as the other 

 Apiocrinidae, in the upper beds of the Oolite. They have not been found 

 in the lower Cretaceous, but again make their appearance in the White 

 Chalk (Bourgueticrinus). They have not as jet been discovered in the 

 Tertiary, hut they, or their allies, have been brought to light in the deep 

 seas of the present day (Rhizoerinus and Calamocrinus). 



It is interesting, in view of the discovery of so many genera of Crinoids 

 by the recent deep-sea explorations, to recall the speculations of D'Orbigny $ 

 on their probable existence in our seas. He says : — 



" Tons ces genres et ces especes qui ont peuple les mers a des epoqnes 

 reculees, parurent longtemps n' avoir pas survecu aux epoqnes geologiques ; 

 an moins, en scrutant les annales de la science etait-on tente de le croire ; 

 mais je crois aujourd'hui qu'il en existe encore de vivantes. . . . 



"M. Saint-Cyr Hotessier ... a bien voulu me communiquer des echantil- 

 lons de breches recentes (de la Guadeloupe). . . . Comme les breches ou 

 se rencontrent ces restes de Crinoides (Bourgueticrinus Hotessieri, D'Orb. ) 

 se torment encore journellement, et qu'elles contiennent seulement des es- 

 peces vivantes aujourd'hui, on doit croire que ce Crinoide important existe 



* NeuesJahrb. f. Mineral., 1890. I. 



t Bull. Mus. Comp. Zool., Vol. XX. No. 6, December, 1890. 



J Histoire Naturelle geneYale el particuliere des Crinoides vivants et fossiles, comprenant la des- 

 cription zoologique el ge'ologique de ces animaux, par Alcide D'Orbigny. 3 e Livraison, Paris, 1840. 



