108 CONTRIBUTIONS TO DEVONIAN PALEONTOLOGY. [bull. 244. 
The fauna is chiefly of interest as showing the presence of a Che- 
mung* fauna after sediments of strongly Catskill type have made their 
appearance in the section. 
FORMATIONAL CORRELATION OF LEROY SECTION. 
By E. M. Kindle. 
The sections which have been described from exposures in the 
vicinity of Leroy give a connected section from the Sharon conglom- 
erate down to the lowest beds exposed in the Towanda anticline, 
aggregating a thickness of 2,902 feet. The section may be divided, 
with reference to its more prominent lithological characteristics, into 
the following divisions: 
General divisions of the Leroy section. 
Feet. 
7. Coarse gray or white sandstone conglomerate (Sharon conglomerate) 20 
6. Soft red shales (Mauch Chunk) 30 
5. Red and greenish sandstones and shales, green beds predominating 
( Oswayo ) 712 
4. Red and green sandstones and shales, the red beds predominating (Catta- 
raugus or Catskill) 653 
3. Drab-colored shales and sandstone with some highly ferruginous bands 
( Chemung ) 400 
2. Purple or reddish sandstone and shale interbedded with heavy beds of 
limestone (Franklindale beds) 160 
1. Gray arenaceous shales and thin bedded sandstones (Chemung) 927 
2,902 
There is nothing in the uninterrupted sequence of sandy shales and 
sandstones which make up the first 900 feet of the section to lead to 
any sudden change in the faunas. We may therefore expect to find, 
as we do in this section, that many representatives of the Ithaca fauna 
have continued on for some time after the appearance of Chemung 
types. The Ithaca fauna is an indigenous fauna in eastern New York, 
having been derived chiefly from the Hamilton. The Chemung rep- 
resents a later development of the same fauna with the addition of 
certain foreign forms, as Spirifer disjunctus. This species first 
appears in the section about 700 feet above the base. Delthyris mesi- 
costalis, which is a characteristic Chemung form, appears near the 
base of the section. The Ithaca element of the fauna is seen in the 
presence of such forms as Sp. mesistrmlis, which indicates an over- 
lapping of the Chemung and Ithaca faunas. The appearance near the 
base of the section of a form of so much zonal significance as Dei- 
thyris mesicostalis with well-developed medial septum seems to justify 
the correlation of the lowest division of the section with the Chemung. 
The Ithaca species which have transgressed the normal upper limit of 
that fauna nearly all disappear in the first 500 feet of the section, 
