ZOOLOGICAL CHABACTEBS. L15 



and separated the truly brachiate Crinoids from the Blaatoida and Cystids, which he 

 proposed to group together as M Anthodiata," though, Like Roemer, he extended 

 Miller's name Crinoiden to include the armless Blastoids, in ignorance of the fact 

 that the foresight of Leuckart had already provided a better one. 



There is much to he said for this classification of Burmeistcr's, the principle of 

 which has been adopted hy Wachsmuth and Springer, as we shall see subsequently. 

 The remarkably unsatisfactory arrangement of d'Orbigny and his countrymen, who 

 grouped the Blastoids and Cystids as families of the Crinoidea equivalent to the 

 Comatulidae and Pentacrinidse, needs no further notice, as it has been superseded by 

 others which give bettor expression to important morphological differences. Claus ' 

 in 187C, and subsequently Zittel and de Loriol, adopted the principles of Roemer's 

 classification, regarding the Blastoids, Cystids, and true Crinoids as orders of the 

 class Crinoidea, this being itself equivalent to Echinoidea, Stellerida (Asterids and 

 Ophiurids), and Holothurians. 



In this country, however, the ideas of Miller and Say. of von Buch and Forbes, 

 have more generally prevailed, and Crinoids, Cystids, and Blastoids have usually been 

 regarded as independent but equivalent groups of the Echinodermata, of the same 

 rank as the Urchins, Holothurians, and Starfishes ; and in accordance with the 

 elevation of the Echinoderms to the rank of a subkingdom, its ordinal divisions 

 have become classes. In the fourth edition of Claus's ' Grundziige,' which was 

 published in 1S80, this rank is assigned to each of the three groups of Stalked 

 Echinoderms, as it is to the Urchins and Starfishes. 



The same course was taken in the Report on the ' Challenger ' Crinoids 2 , but 

 Leuckart's name Pelmatozoa was revived for the Stalked Echinoderms, which, in 

 accordance with his suggestion and the later ones of Huxley and Kay Lankester, 

 were regarded as forming a distinct primary division of the subkingdom. Ludwig 3 , 

 the leading German authority upon Echinoderms, has since adopted this classification, 

 and divides the Echinoderms into two primary groups, the Actinozoa 4 and the 

 Pelmatozoa, the first including four and the latter three classes. This differs 

 slightly from Leuckart's arrangement, in which the Holothurians are separated 

 as Scytodermata from the Actinozoa on the one hand and from the Pelmatozoa 

 on the other. We are inclined to believe that the former is probably the best 

 arrangement ; but whichever of these two systems be eventually accepted, we feel that 

 there can be little doubt as to the value of the Pelmatozoa as a " primary division of 



1 ' Grundziige der Zoologic,' Dritte Autiage (ilarburg und Leipzig), 1S7G, Bd. i. p. 279. 



2 Zool. Chall. Exp. Part xxxii. 1 884, p. 186. 



3 Dr. Johannes Leunis ' Synopsis dt r Thierkunde,' Dritte Autiage, 1886, lid. ii. p. x . 8. 



* This name, which is due to Latreille, was employed by Leuckart for tho Urchins and Stellerida together ; 

 but in this country it is generally used to designate the Corals and their allies, which are known in 

 Germany by Ehrenberg's name Anthozoa. We prefer therefore to adopt the coarse taken by Sir WyviUe 

 Thomson in a Syllabus of his Class Lectures on Zoology which was published at Edinburgh in 1878, and 

 to use "Echinozoa" as a comprehensive term including the Urchins, Stelleride, aud Holothurians. 



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