142 THE VOYAGE OF H.M.S. CHALLENGER. 



IX.— ON THE RELATION BETWEEN THE RECENT AND THE 

 FOSSIL NEOCRINOIDS. 



Onr knowledge of the Crinoids of the Secondary rocks is largely due to the labours of 

 d'Orbigny, Quenstedt, and de Loriol, the last of whom, having completed an elaborate 

 Monogi-aph on the Fossil Crinoids of Switzerland, is now publishing a still more extensive 

 one devoted to those occurring in the Jurassic rocks of France. 



He groups the Neocrinoids into ten families — 



1. Marsupitidse. 



2. Uintacriuidje. 



3. Encrinidie. 



4. Eugeniacrinidse. 



5. Plicatocrinid^. 



G. Apiocrinid^. 



7. Bourgueticrinidie. 



8. Holopodidge. 



9. Pentacrinidae. 

 10. Comatvdidse. 



The first two of these, each based on a single genus, are placed provisionally among 

 the Neocrinoids by de Loriol, who has transferred them from the Palseocrinoids ( = TesseUata) 

 vrith which they were ranked by ZitteL In this step, and also in the establishment of the 

 new family Bourgueticrinid^ for the reception of Bovrgueticrinus, Rhizocrinus, and 

 allied genera, I entirely agree with de Loriol ; but I am not disposed to follow him and 

 Zittel in the association of Hyocrinus and PUcatocrinus into one family, and prefer to 

 consider the former genus as the type of a new family " Hyocrinidse." It has not yet 

 been discovered in the fossil state ; and of the ten families enumerated by de Loriol, the 

 first six in the above list died out at or before the close of the Secondary period ; while 

 all the four others have living representatives. 



Little need be said about the extinct Neocrinoids, except that the association of the 

 Cretaceous Marsiqntes and Uintacrimis mth the Palseocrinoids, the so-called TesseUata, 

 appears to me to be based on a misconception ; and that Encrhms, as might be expected 

 from its stratigraphical position, finds its nearest allies in genera of the Carboniferous 

 and not of the Jurassic epoch, as will be pointed out later. 



The characters of Flicatocrinvs are entirely difi"erent from those of any recent Crinoid, 

 though its calyx has a singular resemblance to those of young Pentacrinidae. The 

 Eugeniacrinidse are a less aberrant group ; but though the symmetrical forms of JEitgenia- 

 crinKS appear to have a considerable resemblance to Rhizocrinus and Bathycrimis in the 

 structure of the lower part of the cup and in the distribution of the canal system, jct 

 such types as Phyllocrinus and the distorted Torynocrinus arc altogether different from 

 any recent Crinoid. 



The Apiocrinidie, represented by some doubtful species in the Lias, flourished exten- 



