SYSTEMATIC PART. I45 



in Marsupites and Uintacrinus ; while Agassizocrinus, Edriocrinus, and the 

 Comatulas are stemless in the adult. Among Blastoids, the stem is wanting 

 in PentapJiyllum, Triccelocriniis and Eleutherocrinus ; and this is the case also 

 in a large number of Cystids. The three divisions undoubtedly are nearer 

 related to each other than to any of the other groups of the Echinoderms, 

 not so much by reason of the stem, as because their habit of life is with the 

 mouth upward, the body lying on its back or growing on a stalk, in contrast 

 with the habits of Starfishes, Ophiurids and Urchins, which crawl about 

 mouth downward, and the Holothurians, which swim with the mouth side- 

 wise. Upon these characters, perhaps, the Echinoderms might be conveni- 

 ently separated into three great groups -, but in that case a new name should 

 be adopted in place of " Pelmatozoa." 



We are now prepared to accept the Crinoids, Cystids, and Blastoids as 

 Separate groups of independent rank ; but what may be their exact relative 

 importance, that is to say, what should be the exact size of the compartments 

 to be provided for them in the scheme of classification, is purely a matter of 

 opinion, and not of great consequence. The tendency of authors is more 

 and more toward recognizing them as groups well distinguished from each 

 other, and they are now ranked generally as independent classes. 



There is in our opinion not the slightest doubt that the " Crinoidea," as 

 proposed by J. S. Miller in 1821, were limited to Brachiate forms, or, to 

 be technically accurate, to the Stalked Echinoderms with ^Particulate arms." 

 This is clearly shown by his definition,* already quoted by us in a previous 

 chapter. While including among his species both recent and fossil forms. 

 Miller did not refer to his Crinoidea a single Cystid or Blastoid, although 

 both must have been known to him. Cystids are abundant at the Dudley 

 locality, from which he described some Crinoids, and a Pentremites had been 

 figured in 1808 by Parkinson in his " Organic Remains," — a work with 

 which Miller was no doubt familiar. The name '' Crinoid," in the strict sense 

 thus employed by Miller, has been sanctioned by the usage of practical natur- 

 alists ever since, and in our opinion all attempts to strip the term of its 

 familiar signification, either by enlarging or restricting its meaning, will 

 prove abortive. If von Zittel, instead of a new name for the Crinoids, had 

 proposed some appropriate term for the larger group, — to include the 

 Crinoids, Cystids, and Blastoids, — it would have been a very desirable im- 

 provement, and we believe would have been generally accepted. 



* Natural History of the Crinoidea, p. 7. 

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