250 
The American Geologist. 
April. 1901 
rhynchoncUoids now referred to Cainarothocchia (Plctlia- 
rhyncha), nearest to C. (P.) plcio pleura Hall. This is one 
of tile interesting representatives of the Saint Helen's Isl- 
and Helderbergian fauna in that it shows transition into 
Oriskanian forms. Dr. Ami has likewise noted this spe- 
cies. 
"Pentamenis vcrncuiW' Donald and Deeks. 
If based on the specimen thus labeled in the Redpath 
Museum, this identification is an error for Spirifer con- 
cinniis. 
Gypidula pseudogalcata (Hall) ? 
The material in the National Museum representing this 
species is very imperfect, but it shows that the form is a 
Gypidula without plications. Since G. pseudogaleafa is 
the only Helderbergian species of this type, the St. Helen's 
Island specimens are provisionally identified with Hall's 
species so characteristic of the Becraft limestone. 
Rcussclaeria acquiradiata Hall. 
The single ventral valve of this species agrees very well 
with the New York specimens of the large Helderbergian 
^(Becraft) Rcnsselacria. 
Chonostrophia uioiitrcalcnsis n. sp. 
Chronostrophia jereiisis n. sp. 
ir- a. 
Am 
EXPLANATION OF FIGURES. 
Figs, a and b, C. luoiitrealensis, a, xentvsLl aspect, b, surface X5. 
Figs, c and d, C. jcrvcnsis, c, ventral aspect, d, surface X5. The 
lines between the figures illustrate the curvature of the 
valves. 
