Lorraine Faunas of New York and Quebec 257 
mens having the same features occur along the Richelieu River, 
at Chambly; a very typical example, collected there by A. H. 
Foord, in 1881, is preserved in the Victoria Memorial Museum, 
at Ottawa, by the Geological Survey of Canada. It is not so cer- 
tain, however, that this is a constant feature. The species is 
very abundant at many localities in the province of Quebec, and 
has a very considerable vertical range, but the subtruncate 
anterior margin appears to be an individual characteristic, rather 
than a prevailing one in the great majority of specimens to be 
referred to this species. Pholidops, apparently of the same type, 
occurs at various localities within two miles west and northwest 
of Vars, about 12 miles east of Ottawa, and also a mile west of 
Edwards station and a mile northwest of Hawthorne station. 
East of Montreal it occurs at Chambly, and St. Hilaire. South- 
west of Three Rivers, it is found along the Nicolet River, south- 
west of Ste. Monique. Here it ranges from 75 to 1065 feet below 
the lowest horizon containing Strophomena planumbona. 
4. Glyptorthis insculpta, Hall 
The type of the genus Hebertella is Hebertella sinuata, Hall, 
from the Maysville division of the Cincinnatian. This type of 
shell is recognized in the Rogers Gap fauna, beneath the Fulton 
layer; in the Greendale division of the Cynthiana formation, 
where one of the species has been described as Hebertella park- 
sensis; in the Trenton of central Kentucky, where one form has 
been described as Hebertella frankfortensis; in the Chazy of Canada, 
where Hebertella borealis occurs; and other species no doubt are 
found in still lower strata. The shell structure is fibrous and 
impunctate, and the surface is marked by fine concentric striae 
and lines of growth, but not by lamellose lines of growth. In 
mature shells, the median part of the brachial valve tends to 
become elevated anteriorly into a low broad fold which in some 
species is quite strongly developed. 
In another group of shells, however, typified by Hebertella 
insculpta, Hall, the shell structure is not only fibrous and impunc- 
tate, but lamellate, and the surface of the shell is marked by la- 
mellose lines of growth. Even in fractured specimens, the la- 
mellose shell structure is readily detected. In the shells of this 
type, so far seen, there is no tendency toward a median fold in the 
brachial valve. Hebertella insculpta occurs in the Richmond; a 
