IN THE RED SANDSTONE OF POTTSVILLE. V 



of tlie genus Anisopus allies them to Cheirolheriiim and the figures of Dr. Deane, although 

 evidently ditTerent, still have some analogy to the same genus. 



These interesting discoveries had not long been made before the scientific world was 

 informed of equally important quadrupedal imprints having been observed in the rocks of 

 the Coal Measures, a Formation considerably lower in the series. In October, 1843, 

 Sir Charles Lyell, in a paper communicated to the American Journal of Science, stated 

 the fact that Mr. Logan had discovered in the "rippled marked sandstones" of Horton 

 Bluff, Nova Scotia, "foot-steps which appear to Mr, Owen to belong to some unknown 

 species of reptile, constituting the first indications of the reptilian class known in the car- 

 boniferous rocks," vol. 45, page 358. Von Meyer, early in 1844, added lo the Fauna of 

 the coal Formation a new reptile which he called Apatcon pcdeslris, the complete skeleton 

 of which he obtained at Miinster-Appel, in Rhenish Bavaria. Towards the latter part of 

 the same year, Dr. King, of Greensburg, Penna., published an account of the imprints 

 discovered by him in Westmoreland county, in the sandstones of the Coal Measures, near 

 to the surface of that formation, (No. 13, Penna. Survey.) This appeared in the Proceed- 

 ings of the Academy of Natural Sciences, December 17, 1844. These " Foot-marks con- 

 sisted of those of a bird and two " Satiria7i reptiles,'''' and were stated to be " near 800 feet 

 beneath the topmost stratum of the coal formation." These were subsequently visited 

 and examined by Sir Charles Lyell, who considered them to belong to the genus Cheiro- 

 lheriiim. Prof. Hitchcock described Thcnnropus heterodaclylus of Dr. King under the 

 impression of its being Batrachian. The tracks, I think, were made by a Sauroid animal. 

 Subsequently to these discoveries, in 1847, Prof. Von Dechen observed in the Goal For- 

 mation of the Saarbriick district several remains of a peculiar genus, which Dr. Goldfuss 

 described under the name Archegosaurus Decheni, and at the same time stated that he 

 considered it as "a crocodilian animal, forming a transition to the lizards, in consequence 

 of the presence of a parietal foramen." After this. Dr. Goldfuss added two other species 

 to this genus, A. medius and A. minor. The largest of the three, the Dechcni, was sup- 

 posed to be about three feet six inches long, and on a further examination he considered 

 the genus to belong more to the Labyrinthodonts, (Cheirotherium,) of the Trias than to the 

 crocodiles. " The peculiarities of the skeleton correspond to those of the skin, which 

 consisted of long, narrow, wedge-shaped, tile-like, horny scales, arranged in rows, which 

 meet on the ventral side in Archegosaurus Decheni at right angles, in A. medius in a curve." 

 Von Meyer considered that the Archegosaurus was nearly allied to the Labyrinthodonts, 

 which Sir Richard Owen had considered as Balrachians. These Von Meyer was now 

 inclined to believe were rather Saurians. It is said that Owen is lately disposed to con- 

 sider the Labyrinthodonls as Saurians arrested in their development; page 55.* In Janu- 

 ary of the present year, a memoir on the discovery of fossil foot-steps by Captain Brick- 

 enden, and of a reptile, by Patrick Duff, Esq., and described by Dr. Mantell, was presented 

 to the Geological Society of London. The specimen discovered by Mr. Duff was " a 

 small four-footed reptile, not exceeding six or seven inches. A distinct impression of a 



• M. Jager says that the Pygopterus lucius of Agassiz is not a fish, but a rpptile, aiul the same as .^rchegc- 

 siiiirus Decheni. (Geol. Soc. Journal, vol. 7, p. 34.) 



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