SYSTEMATIC PART. 145 
in Marsupites and Uintacrinus ; while Agassizocrinus, Edriocrinus, and the 
Comatulz are stemless in the adult. Among Blastoids, the stem is wanting 
in Pentaphyllum, Tricelocrinus and Hleutherocrinus ; 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 “articulate 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 
a work with 
figured in 1808 by Parkinson in his “ Organic Remains,’ 
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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