1921] NATURAL SCIENCES OF PHILADELPHIA. 29 



occur in a matrix containing macerated and obscured remains of 

 vegetation, an occasional fish spine, and minute fragments of bones. 

 A striking characteristic of nearly all the scales found is their highly 

 enamelled coating. By reason of the fragmentary nature of the 

 material, no attempt has been made at identification. However, 

 because of the enamelled surfaces of the scales, there is probably 

 sufficient justification for provisionally classifying the fishes as 

 ganoids. ^^ 



Locahty: Carbonaceous shale. Little Conewago (loc. 3). 



REPTILIAN REMAINS. 



Coprolites (Plate I, figs. 18, 19) are found associated with the 

 fish remains. These are usually of an elongated, oval form, vary- 

 ing in shape, and from 2 to 60 mm. in length. A cross section made 

 through one of these reveals fish scales and microscopic fragments of 

 bones. 



Localities: Shale, York Haven (loc. 4); Carbonaceous Shale, 

 Little Conewago (loc. 3). 



A few bones and teeth have been found in the Trias of York 

 County* Some of these have been referred to species by Cope and 

 Sinclair. 1® No attempt was made by either of these authorities 

 to locate the horizon. The conglomerate layer shown in the sec- 

 tion made along the Big Conewago creek yielded a fragment of a 

 tooth with serrated edges. An extensive search failed to uncover 

 additional fossil remains, but further search may be productive. 



Locality: Conglomerate, Big Conewago (loc. 2). 



TRACKS. 



Reptilian footprints have been reported from the Trias of York 

 County.^^ Two new localities have produced small tracks on thinly 

 bedded micaceous sandstone. These differ from any previously 

 described from this region. They can be referred to three types. 



One consists of two parallel rows of crescent-shaped impressions 

 with the longer diameter at right angles to the trend of the trail. 

 Spread of track 10 mm. and average distance between successive 

 footprints, 4 mm. (fig. 4, no. 1). 



1* Newberry, J. S. Fossil fishes and fossil plants of the Triassic rocks of New 

 Jersey and the Connecticut Valley. U. S. Geol. Survey, Men. XIV, 1888. 



" Cope, E. D. Description of vertebrata from the Triassic formations of 

 the United States. Amer. Phil. Soc. Proc, vol. XVII, p. 232, 1878. Sinclair, 

 W. J. A large Parasuchian from the Triassic of Pennsylvania. Amer. Jour. 

 Sci., vol. XLV, pp. 457-462, June, 1918. 



