AMERICAN GEOLOGY FOSSIL FOOTPRINTS. 629 



ichnites fulicoides. This sumo slab served for several years the pur- 

 pose of a doorstep, and finally passed into the possession of Doctor 

 Hitchcock in 1839. 



An evident feeling- of jealousy oetween tne two gentlemen most 

 concerned is for the lirst time manifested in this paper, a feeling 

 which apparently existed until the time of Doctor Deane's death, and 

 which caused his friends to publish in 1861 the volume entitled Iehno- 

 graphs of the Sandstone of Connecticut River, a quarto volume of 61 

 pages of text and -16 full-page plates. 



Hitchcock covered the entire subject up to the date of his reading 

 this paper (1841), and described the fine large specimen found in the 

 impure limestone of Chicopee Falls, in Springfield, under the name of 

 Omithoidichnites redjleldii, and also several other new species. The 

 resemblance of these to saurian remains was still recognized, but the 

 proof was not regarded as sufficient to refer them unequivocally to 

 quadrupeds. 



In this paper Hitchcock adopted the following classification for 

 tracks or markings of various kinds: 



Order 1. Polypodichnites, or many-footed tracks. 



Order 2. Tetrapodichnites, or four-footed trucks. 



Order 3. Dipodichnites, or two-footed tracks. 



Order 4. Apodichnites, or footless tracks. 



Under the latter term he included certain marks made by fishes, 

 mollusks, and annelid worms. 



In the American Journal of Science for 1845, Doctor Deane had two 

 papers descriptive of footprints found by him and a part of which he 

 thought to be undoubtedly those of batrachians, agreeing in this respect 

 with Hitchcock, as noted above. In his second paper he described 

 and figured tracks made by a batrachian reptile, the method of pro- 

 gression of which, as indicated by the tracks, was by kangaroo-like 

 jumps, the fore limbs not touching the ground. Again, in 1847, 

 Deane had a paper dealing not merely with the tracks, but also with 

 the supposed conditions under which they were formed, the tracks 

 described being in part those of birds and in part those of quadrupeds. 

 Their preservation he regarded as due to the resubmergence during 

 seasons of flood of the mud flats upon which they were formed. 



Through the same medium and this same year Hitchcock reverted 

 once more to the subject and described two new species of thick-toed 

 bipeds, the one renamed Brontozoum (from Ornithoidichiiites) sitti- 

 manium, and the other B. parallelum. In connection with these he 

 described a large and extraordinary track regarded as that of a batra- 

 chian and to which he gave the generic name Otozoum. He regarded 

 the tracks as having been preserved by being silted in by the waves of 

 spring tides. 



