NO. 3 GRAND CANYON FOSSIL FOOTPRINTS — GILMORE 37 



seen on the second digit of the nianus. This form resembles most closely the 

 genus E.vocampc of the Connecticut Trias, but is a generalized track which 

 almost any small amphibian, such as a modern salamander for instance, 

 might make and while it may for convenience be placed within the mentioned 

 genus, genetic relationship with the creatures that made the tracks so desig- 

 nated is not of necessity implied. 



Specific characters. — Manus somewhat smaller than the pes, with three 

 well-defined, radiating digits, the middle one of which is directed forward. An 



B A 



\ I 



>.«' 



.1 



.'J 



s'/ 



Fig. 15.— BatrachiclDiHs dclicatiila (Lull). No. 11,519, U. S. N. j\I. 

 A, diagram of trackway showing normal track. B, showing track- 

 way made by the hindfeet only. Note that the stride has lengthened 

 and the trackway is narrower than in A. Dotted lines connect im- 

 pressions made by the hindfeet. Both figures ^ natural size. 



obscure impression of an additional digit lying on the imier side of and 

 more nearly parallel to the second is indicated. There is also at the base of 

 the second digit what may represent a palmar pad. It may, however, be acci- 

 dental, as there are other such on the slab. 



Pes. — The four phalangeal impressions are more or less ovoid without 

 indications of claws or phalanges and, except for the first, curve slightly 

 outward. There is a faint mark which may indicate a fifth digit. The pes 

 impression lies immediately beliind that of the manus and a little apart from 

 it as the figure indicates. There lies in advance and to tlie left of the impres- 



