ICHNOLOGY 105 



mid toe, but are not identical with those of any known 

 Batrachian or other reptile. They show a papillose integu- 

 ment as in some mammals, but also like that on the sole of 

 certain Geckos, and which may be another mark of sauroid 

 departure from the modern batrachian type. The proximity 

 of the right and left prints to the median line indicates a 

 narrower form of body, or its greater elevation upon longer and 

 more vertical limbs, than in tailless Batrachia. In the attempt 

 to solve the difficult problem of the nature of the animal which 

 has impressed the new red sandstone with the cheirotherian 

 footprints, we cannot overlook the fact, that we have in the 

 Ldbynnthodons also batrachoid reptiles, differing as remarkably 

 from all known Batrachia, and from all other reptiles, in the 

 structure of their teeth ; both the footsteps and the fossils are, 

 moreover, peculiar to the new red sandstone ; the different 

 size of the footprints referred to different species of Cliciru- 

 theria correspond with the different size of ascertained species 

 of Ldbyrinthoclon ; and the present facts best support the 

 hypothesis, that the footprints called "cheirotherian," are 

 those of labyrmthodont reptiles. 



Genus Otozoum. — The footprints in the red sandstones, 

 probably of liassic age, in Connecticut, described by Prof. 

 Hitchcock under the above name, equalled in size the largest 

 of those of the Chcirothcrium (Oh. Hercules), but the hind 

 foot had but four toes, whilst the fore foot had five toes. It 

 would seem that the hind foot, which was larger than the fore 

 foot, obliterated the print of that foot, by being placed upon it 

 in walking. In the few instances of the fore foot print the toes 

 are turned outward, and the fourth and fifth seem to have been 

 connate at their base. An impression of a web has been clearly 

 discerned in the hind foot. Only one toe on this foot shows a 

 claw, the rest are terminated by "pellets," as in the Batrachia, 

 to which family Dr. Hitchcock refers these footprints, though 

 with a surmise of the possibility of their marsupial nature.* 

 * Icbnology of Massachusetts, 4to, 1858, p. 123. 



