BRACHIOPODA. 
221 
ORTHIS, Dalman (as restricted). 
I. Group of Orthis callactis, Dalman. 
* 0. costalis, Hall. 
f * 0. orthambonites, Billings. 
* 0. Euryone, Billings. 
* 0. Hippolyte, Billings. 
* 0. disparilis, Conrad. 
* 0. tricenaria, Conrad. 
* 0. flabellulum, Sowerby 
* 0. Davidsoni, de Verneuil.. 
Chazy. 
Quebec. 
Quebec. 
Quebec. 
Trenton. 
Trenton and Hudson River. 
Niagara. 
Niagara. 
* 0. sequivalvis, 
* 0. plicatella, 
*[?]0. Ella, 
* 0. fissicosta, 
* 0. Jamesi, 
* 0. Kankakensis, 
*[?]0. sectostriata, 
* 0. triplicatella, 
* 0. Whitfieldi, 
* 0. dichotoma, 
[??] 0. aurelia, 
PLECTORTHIS 
(nom. propos). 
II. Group of Orthis plicatella, Hall. 
Hall . Trenton and Hudson River. 
Hall . Trenton and Hudson River. 
Hall .. Hudson River. 
Hall . Hudson River. 
Hall . Hudson River. 
McChesney . Hudson River. 
Ulrich . Hudson River. 
Meek . Hudson River. 
N. H. Winchell . Hudson River. 
Hall Hudson River. 
Billings . Lower Devonian. 
t This species was identified by Billings with 0. orthambonites, Pander; but that author used Ortham¬ 
bonites only as a generic term, though it was subsequently taken by von Bcch and von Eichwald as a 
specific designation to include all the species referred by Pander to this genus. As a specific term, it must, 
therefore, be accredited to von Bdch, and it is synonymous with some one (it is impossible to say which) of 
Pander’s species. It appears to be quite distinct from the 0. calligramma, var. orthambonites, de Verneuil, 
with which the Quebec species is compared by Mr. Billings, and it should therefore receive a new name. 
