vw 
we) 
met with in other countries ; but, in their number and 
variety, the valley of the Connecticut abounds above 
all places hitherto investigated. 
Twenty years have elapsed since the study of Ichno- 
logy has been prosecuted in this country; and, in this 
period of time, about forty-nine species of animal 
tracks have been distinguished in the locality men- 
tioned, according to President Hitchcock ; which have 
been regularly arranged by him in groups, genera, and 
species. 
I propose now to lay the specimens, recently 
obtained, before the Society, as a slight preparation 
for the more numerous and more valuable articles 
which they are soon to receive. 
The traces found on ancient rocks, as has been 
shown in the previous article, are those of animals, 
vegetables, and unorganized substances. The traces 
of animals are produced by quadrupeds, birds, lizards, 
turtles, frogs, mollusca, worms, crustacea, and zo- 
ophytes. ‘These impressions are of various forms: 
some of them simple excavations; some lines, either 
straight or curved, and others complicated into various 
figures. 
President Hitchcock has based his distinctions of 
fossil animal impressions on the following characters, 
Viz. : — 
