156 THE COAL MEASURES AMPHIBIA OF NORTH AMERICA. 



In none of the species of this genus have the usual 3 thoracic shields (clavicles 

 and interclavicles) been observed. The abdominal scutae, on the other hand, are 

 much like those of Sourer peton, being, however, smaller. 



The species formerly described by Cope in the genus Colosteus are included in 

 Sa tiro pleura, where they find their closest allies. 



There are 7 species belonging in this genus: Sauropleura digitata Cope, S. new- 

 berryi Cope, S. foveata Cope {Colosteus), S. scutellata Newberry {Colosteus) (type 

 of genus), S. pauciradiata Cope {Colosteus), S. longidentata Moodie, S. enchodus 

 Cope {Anisodexis) . The species described by Cope as Sauropleura latithorax is 

 regarded as belonging to a distinct genus, Saurer peton. 



Sauropleura scutellata Newberry. 



Newberry, Proc. Phila. Acad. Nat. Sci., p. 98, 1856 (Pygoplerus sculellatus). 

 Cope, Proc. Phila. Acad. Nat. Sci., p. 215, 1868. 

 Cope, Trans. Am. Phil. Soc., p. 22, 1869. 

 Cope, Geol. Surv. Ohio, 11, pt. 11, p. 402, 1875. 



Type : Specimen No. 8669 G, American Museum of Natural History. 



Horizon and locality: Linton, Ohio, Coal Measures. (Plate 14, fig. 3.) 



This species was first described by Newberry as a fish belonging to the genus 

 Pygopterus. Cope later placed it under the genus Colosteus and clearly showed its 

 amphibian characters. The genus Colosteus was, however, based on a misconcep- 

 tion. Cope in 1897 and Hay (317) referred the species to Sauropleura, where it 

 is retained. The species is represented by a single individual preserved on a block 

 of coal from Linton, and is also indicated by an interclavicle and its obverse; this 

 element is of larger size than that of the type and was referred by Cope to Colosteus 

 pauciradiatus . The characters of the plate are, however, so identical with those of 

 the interclavicle in the type specimen that it is unhesitatingly referred to the pres- 

 ent form. 



The type specimen consists of the supero-lateral view of a crushed cranium with 

 the anterior part of the body, exhibiting the interclavicle and the ventral scutella- 

 tion. No limbs have been observed in this species. The mandibles are crushed 

 across the cranivun in such a way as to obscure its structure. The boundary of the 

 left orbit is doubtfully determined as being a little back of the median line of the 

 skull. There are small teeth present on the mandibles, but their number can not be 

 determined. The cranial elements are sculptured with radiating grooves and 

 ridges, but these are weakly developed. The snout is broad and but little narrower 

 than the base of the skull. (Plate 21, fig. 5.) 



The interclavicle, somewhat displaced, is the only element of the pectoral 

 girdle preserved. It is peculiar in the possession of a backward extension which 

 shows a beveled edge. The plate is ornamented by radiating grooves and ridges 

 which are strongly developed. The larger specimen of an interclavicle shows the 

 same characters as the one described, and it differs only in being about twice as 

 large. There are no traces of limbs. 



The ventral armature of the body is rather weak as compared to that of Sau- 

 ropleura pauciradiatus, but it is still composed of closely packed scutes arranged 

 en chevron. The character of the ventral armature and the sculpturing of the inter- 



