Geology, be. of the Connecticut. 7 
At Sunderland these impressions occur in bituminous 
shale, which often contains a little mica, and generally a 
‘ antity of iron pyrites, disseminated through the rock. 
hey occur at Witmore’s ferry in the north part of Sunder- 
land, in the bank of the river. They are found most‘abun- 
dant at the lowest water mark, at which titne two men, in 
less than half a day, dug out for me nearly fifty specimens. 
Sometimes a layer of semi-crystalline dark colored carbo- 
nate of lime, less than one twentieth of an inch thick, lies | 
between the layers of slate. The substance of the fish is” 
usually converted ir:to coal, the thickness of which is rarely. 
more than one tenth of an inch in any part, and the color is” 
black. In some instances, however, the carbonate of lime 
above mentioned covers the fish, and has taken the place of 
the matter of the fins and scales and their original light 
grey color is preserved so perfectly as to resemble a fish 
just taken n out of the pe ‘Some of the specimens 
appear contorted; in the form of the fish is verel:. 
ly lost, ae fins and scales and bones, being sc 
about promiscuously, as if the fish had perished i in violent 
atenbele® or the rock had been disturbed after its imprison- 
ent. Yet, in the same specimen that contains one thus 
mitnibatid another will appear not more than a foot distant 
which is whole. I have found four or five specimens in 
which the fishes (both of them distinct,) lie across each oth- 
er; sometimes a very thin layer of shale, and sometimes 
none, separating them, Ihave another specimen, three feet 
long and fifteen inches wide, containing seven distinct impres- 
sions. The shalein which these ichthyolites occur,when rub- 
bed or held in a fame, exhales a strong bituminous odour.* 
Among the impressions hitherto obtained, I can easily 
discover three distinct species that have scales.* Two of 
these are represented on the accompanying plate; but the 
third was so much mutilated, that I did not attempt to de- 
lineate it. Fort at the best it is no easy matter to represent 
them so exactly as to be of use. They are usually a little 1 in- 
distinct on their border, 
ig. 1. represents a species that is rare. 
Fig. 2. shows the most common species. There ean be 
no doubt that this differs generically from the last. . 
oie 
tito such a smell is exhaled from the bituminous Kimestone in 
Southington 
*See the end. 
