Cope. ] 52 [May 20, 1877. 
resembles Oreodon, but in this genus the internal convolution is continu- 
ous with the supraorbital.* 
EXPLANATION OF PLATE. 
Brain of Procamelus occidentalis from a cast, two-thirds the natural size. 
Fig. 1. View of the left side. 
Fig. 2. View of the superior surface. 
Fig. 3. View of the inferior surface. 
On the Vertebrata of the Bone Bed in Eastern Lilinois. 
By E. D. Cops. 
Read before the American Philosophical Society, May 20, 1877. 
It is already well known that a few years ago, Dr. J. C. Winslow dis” 
covered in the Eastern part of the State of Illinois, a bone bed containing 
the fragmentary remains of reptiles and fishes. From some of this 
material placed in my hands, I identified four species of Vertebrata, two 
Rhynchocephalian reptiles, one a Dipnoan and one Selachian fish}. These 
were named, Cricotus heteroclitus, Clepsydrops collettii, Ceratodus vinslovit, 
and Diplodus sp. indet. It was stated in connection with the descriptions 
of these, that they indicate Triassic or Permian age for the bed in which 
they were found, since on the one hand Reptilia have not been found in 
the coal measures, nor on the other hand has the genus Diplodus been 
found above the Carboniferous series of rocks. 
Doctor Winslow, in response to my inquiries, has sent for my examina- 
tion another series of these fossils, which contains several species not 
previously known from the formation. Subsequently William Gurley 
discovered another exposure of the bone bed, and obtained a number of 
useful specimens, including some of species not previously known, which 
he also kindly placed at my disposal. To both these gentlemen I desire 
to express my sense of the obligation under which they have laid me. 
Descriptions of some of the species are now given ; a complete account of 
the fauna is reserved for an illustrated memoir now in preparation. 
STRIGILINA LINGU4FORMIS Cope, gen. et sp. nov. Petalodontidarum. 
Char. Gen. The tooth is a flat osseous plate whose outline is pyriform, 
the wider end recurved in one direction as the transverse cutting edge ; the 
other extremity narrowed and recurved in the opposite direction as the 
root. The side from which the cutting edge arises is crossed by numerous 
plice from the base of the root to near the base of the cutting edge ; the 
Opposite side is smooth. 
The genus appears to resemble most nearly the Climazxodus of McCoy, 
* Leidy, Extinct Fauna, Dak, and Nebraska, pl. xiv, fig. 11. 
+ Proceedings Academy Philadelphia, 1876, p. 404. 
