374 



latter locality appear to lie above the 700 feet of sandstone constituting 

 Division 0, and are, therefore, in the foregoing descriptions of species, 

 referred to Division P. Taking these three localities to be on the same, 

 or nearly the same, horizon, we have from them, in addition to a few not 

 yet described, the following 48 species : — 



Lingula Nympha 



" lole 



" Cyane 

 Acrotreta gemma 

 Ortbis delicatula 



* Strophomena Aurora 



*' imbecilis 



" decipiens (?) 



Camerella parva 



" variaas * 

 Rhyncbonella Corintbia 

 Pleurotomaria sponsa 



* Murcbisonia simulatrix 



* " Augustina 



* Maclurea crenulata 



* " acuminata 

 Ecculiompbalus superbus 



* Ortboceras piscator 



* " Allumettense 



* Batbyurus Nero 



" breviceps 



Asaphus Huttoni 

 " Morrisii 

 " quadraticaudatus 



Nileus macrops 

 " scrutator 

 Illaenus fraternus 

 " consimilis 

 Endymionia Meeki 

 Holometopus Angelini • 

 Harpides Atlanticus 



" concentricus 

 Sbumardia glacialis 

 Cbeirurus Polydorus 

 " perforator 



'= Sol 



Ampbion Barrandei * 

 Triartbrus Fiscberi 

 Telepbus Americanus 

 Encrinurus mirus 

 IJemopleurides Panderi 



" Scblotbcimi 



Ampyx Ireviusculus 

 " normalis 

 " Rutilius 

 " semicostatus 

 Agnostus galba 

 " Fabius 



In the above list those with an asterisk before them are found in some 

 one or more of the Divisions beloAv N ; those with an asterisk after them 

 occur in the grey and white limestones of Division P, at Cow Head. 

 Camerella varians is a Chazy species. Orthocej'as Allumettense is both 

 Chazy and Black River. Holometopus Angelini, Endi/niionia Meeki, and 

 Cheirurus Sol occur in the Quebec group of Canada East. We find here, 

 for the first time, among American trilobitcs the peculiar type of Cheiru- 

 rus, with a spine upon the glabella — . 2^ erf orator (ante, p. 287). Another 

 of the same structure, C. glauciis, was discovered in the Quebec group, 

 in the township of Stanbridge ; and a third, C. Satyrus, in the Chazy, at 

 Montreal, by T. C. Weston, last year, 18G4 (ante, p. 323). This type 

 has been known for several years among the Russian trilobites by SjjJice- 

 rexochus cephaloeeros (Nieskowski) :=: Ze</ms triplicatus (Eichwald), 

 which occurs in the Pleta limestone. The genus Triarthrus has not 

 heretofore been found below the Trenton in America. Rcmopleurides 

 occurs in the Chazy, and Amj^hion in both Chazy and Calciferous ; but 



