364 APPENDIX TO PARTS I AND II. 
Slates. There is a band of argillaceous rocks that are unlike, in their physical char- 
acteristics, any we have described, which is found on both sides of Kennebago lake. 
The most southern outcrop seen is on Spotted mountain, south of John’s pond; the 
most northern, on Kennebago East mountain. The rock is generally thick-bedded. 
Sometimes it has the appearance of an argillaceous sandstone, and it is sometimes a 
little micaceous; and often the finest and most purely argillaceous bands pass sud- 
denly into a-slate conglomerate. The argillaceous rock on the ridge between John’s 
pond and the south end of Kennebago lake breaks up into fragments more like shale 
than slate. The strike of this rock is N. 40° W. 
Slate Conglomerate. The transition of the slate into conglomerate is so sudden that 
we do not suspect its presence until we see the boulders or ledges where the change 
occurs. Boulders of slate conglomerate are abundant on the southern shores of Ken- 
nebago lake, and outcrop in the vicinity of Flatiron pond. 
Calcareous Sandstone with Fossils. Several years ago Mr. H. P. Dill found boulders 
of fossiliferous rocks along the river in Phillips; hence it has long been known that 
fossiliferous bands existed somewhere in this section. The rock seen in the vicinity of 
Kennebago lake is not the same as the boulders of Phillips, though further exploration 
may show that they are found here; but it seems more probable that the ledges from 
whence the Phillips boulders are derived are in some other locality, since the Phillips 
boulders are a pure sandstone, with fossils of Lower Helderberg types, while here the 
rock is a calcareous sandstone, with some fossils that are found with the Oriskany in 
the vicinity of Parlin pond. The change, however, does not appear to be any greater 
than it is between Parlin pond and Moose river. It has long been known that the line 
of demarcation between the Lower Helderberg and Oriskany in Maine is not so well 
defined as it is in New York. At Kennebago lake the number of species is quite lim- 
ited, and they can scarcely be distinguished except upon the weathered edges of the 
rocks where some of them are well brought out. 
The fossiliferous rocks here are probably limited to the area north of Spotted moun- 
tain between Flatiron pond and the bridle-path. 
Glacial Drift. The study of drift in a region entirely covered by forests is more dif- 
ficult, even, than the study of the ledges. In the vicinity of Rangeley lake, however, 
where there are farms, the absence of stratified drift is generally very noticeable. The 
most common boulders in the country about the east end of Rangeley lake are diorite ; 
and these are derived chiefly from the numerous dykes in the west part of the town of 
Rangeley. There are very few boulders except of diorite on the bridle-path to Kenne- 
bago until we get within three miles of the lake, when we have those of slate conglom- 
erate, calcareous sandstone, fossiliferous, and a few granite boulders. 
About ten miles north of Kennebago lake, particularly on the west side of the river, 
we find a remarkable collection of boulders. They consist of sandstone schist, serpen- 
tine, and chlorite, with a few granite boulders; but as we go northward, the granite 
boulders increase, and soon they begin to predominate, and the others disappear alto- 
gether. Some of these boulders are of enormous size, and are probably derived from 
