RR. P. Whitfield—Age of Bernardston rocks. 369 
_ age, the forms mostly resembling those from the New York 
ee ey Ca ae ee ee 
Chemung group. 
In the spring of 1882 we received at the museum a collection 
of rocks and fossils from near Littleton, N. H., sent by Pro- 
fessor C. H. Hitchcock, who has kindly permitted me to use 
the evidence furnished by them in this connection. Among 
them I recognize the corals Halysites catenulata and Favosites 
Magarensis, also a finer form of Favosites which I identified, 
with but little doubt, with Astrocertum venustum Hall, and an 
undetermined Cyathophylloid coral. There are also many frag- 
ments of a Pentamerus, which I identified without question with 
P. nysius H. & W. (24th Rept. State Mus. N. Y., p. 184. 
pl. x, fig. 1-7 of 27th Rept. State Mus.), a type of Pentamerus 
Which ranges from the Clinton to the Guelph limestones, but 
Which is not known above the latter horizon. rom this 
assemblage of fossils.there can be no doubt of the Middle 
Silurian age of these Littleton limestones (probably Niagara) ; 
and as they were supposed, from stratigraphical evidence 
alone, to be the same as the Bernardston limestones before the 
ils were examined, I think these are strong reasons for not 
only making them equivalents, but also for considering both 
48 of the age which I have assigned to them. 
apparent. The calcareous material I have attributed to a 
e Same series. with 
fxaminations correct my inference as to one oO : 
rofess6r _Emerson hopes to make further discoveries, that will 
AM. Jour. Sct.—Tuirp Sertes, VoL. XXV, No. 149.—May, 1883. 
25 
