Raymond : Gastropoda of the Chazy Formation. 169 



minable, Capulus auriformis was not from the Chazy, and Bucania 

 rotundata is the same as Bucania Sulcatina. 



The revised list of gastropods up to the year 1847 includes Maclur- 

 ites magnus Lesueur, Scalites angulatus Emmons, Raphistoma striatum 

 (Emmons), Raphistoma stamineum Hall, Bucania sulcatina (Em- 

 mons), Archinacella deformata (Hall), and Trochonema biangu latum 

 (Hall). 



In the l( Prodrome de Paleontologie," 1850, d'Orbigny substi- 

 tuted the name Murchisonia subabbreviata for Hall's specific name 

 abbreviata, the latter name having been previously used for a species 

 of Murchisonia by de Koninck. 



In the " American Geology," 1855, Emmons added one species, 

 Straparollus angulatus. No figure was given, but there is little doubt 

 from the description, that the name is a synonym for Raphistoma 

 stamineum. 



In 1859 Billings recognized twenty-one species of gastropods in the 

 Chazy of Canada, but described only nine of them. These were : 

 Pleurotomaria docens, Pleurotomaria calyx, Pleurotomaria immatura, 

 Pleurotomaria crevieri, Pleurotojnaria pauper, Murchisonia infrequens, 

 Murchisonia asper, and Maclurea atlantica, all new species, and 

 Murchisonia perangulata r < Hall. Of the eight new species only three, 

 Pleurotomai'ia docens, Pleurotomaria calyx, and Pleurotomaria cre- 

 vieri, were figured. As will be shown in the following pages, Pleuro- 

 tomaria docens is probably Liospira. Pleurotomaria calyx, Pleuroto- 

 maria crevieri, and Pleurotomaria pauper seem to be the same as 

 Raphistoma stamineum. Murchisonia infrequens and Murchisonia asper 

 are known only from the types, which are figured for the first time in 

 this article. The list is thus reduced to six species, making a total of 

 thirteen species of gastropods described from the Chazy up to the year 

 i860. 



In the " Paleozoic Fossils of Canada," Volume 1, 1865, Billings 

 described two species of gastropods from the " Chazy or Black River " 

 at the Mingan Islands, and two from a similar formation at Phillips- 

 burgh, Canada. None of these species have been found in the typical 

 deposits in the Champlain Valley, and their exact horizon is still 

 uncertain. 



Metoptotna montrealensis was described in the same volume from 

 specimens obtained at Montreal, Canada. This species, which belongs 

 to the genus Scenella, occurs in the Champlain Valley, and is the four- 

 teenth of the described species now recognizable. 



