prosser.] CONCLUSIONS. 75 
regard the Portage series as absent from this district. In this view 
of the matter I am influenced by several considerations, the chief of 
which are : 
"First. The occurrence of characteristic Chemung fossils throughout 
the entire interval. 
"Second. The total absence, so far as my observation has extended, 
of all the characteristic Portage fossils, not even a single Fucoid 
having been seen. 
"Third. The Chemung character of the rocks considered lithologi- 
cally, there being a total absence of those interstratified, hard, blue 
sandstones, which distinguish the Portage from the Chemung." 1 
While in the following report on central Pennsylvania is the state- 
ment, "I have found it impracticable to separate the Portage from the 
Chemung by any well-defined characters that would apply throughout 
the district'; although it is very probable that 800 to 1,000 feet of the 
beds in the lower part of the group are the equivalents of the Portage 
beds in New York." 2 In a recent letter Prof. White states that he 
wishes the above statement to apply to Monroe and Pike Counties, and 
that the lower part of the formation called Chemung in those counties 
corresponds to the Portage of New York." The professor says: "I 
would let the Chemung epoch end with the appearance of the first red 
bed, and confine the Portage to the basal, sparingly fossiliferous, flaggy 
beds, which I find 1,000 to 1,500 feet thick above what I have in Penn- 
sylvania, termed the Genesee." 4 
Prof. Claypole described rocks containing Cardiola speciosa (now 
Glyptocardia) in Perry County, which are apparently quite similar to 
the portage of central and western New York: 5 while Prof. Lesley 
says, " On the Delaware Eiver, in Pike, Monroe, and Carbon counties, 
as well as eastward toward the Hudson, and around the eastern and 
northern foot slope of the Catskill Mountains, in New York, the Port- 
age formation can not be recognized as distinct from the overlying 
Chemung. In nearly 2,000 feet of strata from the Genesee black 
slate upward, no characteristic Portage fossil has been seen. Not a 
single seaweed has been found. All the shells are of Chemung type. 
There is a total absence of those hard, blue sandstones which distin- 
guish the Portage in New York." 6 
From the preceding part of this paper we learn that the fossils of 
this formation are not characteristic Chemung species; but that they 
constitute a modified Hamilton fauna, similar to the faunas that occur 
'G fi , 1882, p. 104. 
2 G 7 , 1883, p. G8. In the descriptions of the section along the North Branch Railroad, near Rupert 
(p. 70), and the Fishing Creek (p. 228), in Columbia County, it is stated that Portage rocks maybe 
present. 
3 Letter of Fehruary 22, 1892. * 
"Letter of January 19, 1892. 
5 F'^, 1885, p. 69. 
"Sum. Desc. Geol. Penn., Vol. II, 1892, pp. 1304, 1365. 
