Wachsmuth and Springer—Silurian Urinoids. 5b 
Oca.—Considering that Maté and Coca find place in this vol- 
ume, although perhaps rather employed than cultivated (at least 
(Garcillaso, Comment., b. v, c. 1; b. viii, ¢ 10.) J. de Acosta, 
the Indies, lib. iv, c. 18 
ur notes upon plants cultivated for their herbage, tubers, 
Toots, etc., have run to such a length, that the remainder, con- 
cerning some plants cultivated for their fruits and seeds, must 
be left for another article. 
Art. XXVIII.—Remarks on Glyptocrinus and Reteocrinus, two 
Genera of Silurian Crinoids; by CHARLES WACHSMUTH and 
FRANK SPRINGER. 
In the second part of our Revision of the Palsocrinoidea, at 
Page 185, and following, we undertook to define the character 
and relations of Giyptocrinus and allied genera, in suc ma 
her as to render it possible to group the species thereunder with 
Some approach to their natural order, As is well known to 
every one who has attempted to identify the species, the Amer- 
can Silurian Crinoids are an extremely difficult group to 
understand. There are a few well marked species, of whic 
sine number of species have been described by Billings, a 
scar 
Conclusions would prove entirely satisfactory, even to ourselves. 
d Reteoerinus has 
S 
