338 Prof. 0. C. Marsh — Footprints in the Coal-measures. 



fore feet, and four on those behind. The fore feet were considerably 

 smaller than the hind feet. The impressions made by the latter 

 are nearly all separate from the anterior footprints, although at 

 times slightly overlapping them. 



The nature of the animal indicated by these impressions can at 

 present be a matter of conjecture only, but the probabilities are in 

 favour of its reference to the Amphibians rather than to the true 

 Beptilia. As it is evidently distinct from anything hitherto described, 

 the above name is proposed for it. 



Limnopus vagus. PI. XT. Fig. 2. 



In Fig. 2, Plate XI., a second series of footprints is represented, 

 somewhat larger than those above described, and evidently made by 

 a very different animal. The front feet had four functional toes, 

 while those behind had five, all well developed. The impressions 

 of the hind feet, as a rule, overlap those of the corresponding fore 

 feet. No indications of a tail can be detected. In length of stride, 

 and in the distance between the footsteps of the right and left 

 sides, the present series is proportionately about the same as those 

 above described, although the animals differed much in size. They 

 were probably both Amphibians, and may have been nearly allied. 



Dromopus agilis. PI. XI. Fig. 3. 



The third series of footprints shown on Plate XL Fig. 3 is of 

 special interest, and indicates an animal very distinct from the two 

 already described. 



A striking feature in the fore and hind feet of this animal was the 

 long, slender digits, terminated by sharp claws. Another point of 

 interest, as recorded in the footprints, is that the animal in walking 

 swung the hind feet outward, and so near the ground that the ends 

 of the longer toes sometimes made trails in the mud, marking 

 accurately the sweep of the foot. This would seem to indicate a 

 comparatively short hind leg, rather than the long slender one which 

 the footmarks themselves naturally suggest. 



The animal that made these interesting footprints was probably 

 a Lacertilian rather than an Amphibian, but there is also a possibility 

 that it was a primitive Dinosaur. 



Allopus littoralis. PI. XI. Figs. 4, 4a. 



Besides the footprints above described, which pertain to animals 

 of comparatively small size, there are several other series in this 

 collection made by very large animals, which were probably all 

 Labyrinthodonts. These tracks were made on the same beach, and 

 at about the same time, as the small footprints, but not all under the 

 same circumstances. The largest animal thus represented appears 

 to have walked on one part of the beach that was quite firm, leaving 

 very shallow footprints, and again to have traversed another part, 

 quite near the first, but slightly covered with water, or at all events 

 so soft that deep impressions were made by the feet, while the toes 



