0. C. Marsk — Footprints in the Coal Measures. 83 



the long, slender digits, terminated by sharp claws. Another 

 point of interest, as recorded in the footprints, is that the ani- 

 mal 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 prob- 

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

 a possibility that it was a primitive Dinosaur. 



Allojpus littoralis, gen. et sp. nov. 



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 foot- 

 prints, 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 of 

 the hind feet also left deep trails as they swung outward at 

 each step. On Plate II, figures 4 and 4a, these two kinds of 

 footprints are represented. They show the stride of the ani- 

 mal, and, as put together, also denote the width between the 

 footprints of the two sides, so that the series can be compared 

 with the others on the same plate. 



These tracks show that the animal had five toes in the fore 

 feet and four behind. The hind feet show a distinct impres- 

 sion of a sole. There is no imprint of a tail, even where the 

 mud appears to have been deep. 



Bar opus lentus, gen. et sp. nov. 



The most abundant of the large footprints are represented 

 by several series, which are remarkably uniform in stride and 

 in width between the right and left rows. One of these series 

 is represented on Plate II, figure 5, and this is typical of the 

 others. The animal that made these footprints evidently had 

 four functional toes in front and the same number behind. 

 On the inner side of each foot, however, there was a projection, 

 which, in the hind feet, was quite prominent and characteristic, 

 but can hardly be interpreted as the imprint of the first digit. 

 Nearly all these footprints show a distinct impression of a 

 sole. This is usually faint in the tracks of the fore feet, but 

 strongly marked in those behind. 



