RETEOCRINID&. WE 
Distribution. — Age of the Trenton and Hudson river groups. Restricted 
to America. 
Remarks. — According to Billings, the calyx of Reteoerinus stellaris, the 
type of the genus, consists of a reticulated skeleton, composed of incomplete 
or rudimentary plates, each consisting of a central nucleus, with three to 
five stout processes radiating from it. Of such plates he describes three 
rings of five each, corresponding in position with infrabasals, basals, and 
radials of other Crinoids, and he states that the genus in general structure 
agrees with Cyathocrinus, Dendrocrinus, and allied forms. 
It would seem at first sight that this description does not apply to 
“ Glyptocrinus”” Onealli and the other species that have been referred to this 
genus, as they have numerous interbrachials and interdistichals which Bil- 
lings failed to notice. These plates, however, are actually present in the 
type specimens, having been exposed by additional cleaning. Looking at 
Reteocrinus Onealli in its usual preservation, with its deep interradial areas 
covered by matrix, it corresponds well with the original description. The 
specimens in that state seem to have but three rings of plates in the calyx, 
and free brachials from the radials up. 
Miller refers to Leleocrinus only Billings’ two typical species, placing the 
other three under Gaurocrinus. We cannot discover any ground for generic 
separation of the Ohio and Canada species. It is true Reteocrinus stellaris has 
a third costal, but Miller himself did not attach much importance to this 
character, for he grouped Reteocrinus jimbriatus with but two costals, along 
with P. stellaris, which has three. 
In amending the genus Refeocrinus in 1881,* we referred to it the follow- 
ing species: Glyptocrinus Baert Meek, Glyptocrinus cognatus Miller, Reteocrinus 
fimbriatus Billings, Reteoerinus gracilis Wetherby, Glyptocrinus Onealli Hall, 
Glyptocrinus Richardson’ Wetherby, and Reteocrinus stellaris Billings. We 
afterwards + withdrew Reteocrinus Baeri, which we found to be a Xenocrinus, 
and Reteocrinus Richardsoni, which we placed under Canistrocrinus ; and we 
added Gaurocrinus magnificus S. A. Miller.  Reteoerinus cognatus is probably 
a large R. Onealli, and R. gracilis a synonym of Plychocrinus parvus. 
* Revision, Part IT., p. 192. 
+ Revision, Part III., p. 96. 
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