324 Ornithichnohgy, 



(Fig. 20,) the pea-hen, (Fig. 19,) and the turkey, (Fig. 18,) we 

 see the hind toe turned inward, almost exactly as in the fossil spe- 

 cimen, as shown on the Proportional view of the Ornithichnites 

 appended. But in the foot marks of a bird, probably of the genus 

 Tetrao, that I lately met with, (see Fig. 13,) the hind toe seems to 

 be merely a prolongation of the middle toe backwards. In the tracks 

 of the hen, exhibited in Fig. 20, it will be noticed, that the hind 

 toe is seen only in some of the tracks, because it is situated so high 

 up the tarsus, that it made an impression only when the bird sunk 

 deep into the mud. In the tracks of the pea-hen, the hind toe ap- 

 pears sometimes only as an insulated and rounded impression, as if 

 made by the end of a stick ; because of its peculiar position, form, 

 and direction, in that bird. 



These facts render it probable, that some of the specimens of Or- 

 nithichnites, which I regard as produced by a three toed bird, may 

 have been made by one with four toes; indeed, in some instances, 

 in which I had referred the specimen to O. diversus, careful cleav- 

 age has brought to light the fourth toe. Yet I am confident that 

 such a discovery would rarely be made. And in regard to the larger 

 tracks, I have not noticed any thing that resembles a fourth toe, 

 even if it should turn out that O. diversus is possessed of one. 



To the examples above named of living birds, I might have add- 

 ed that of the whooping crane, [Ardea Americana^ the tallest bird 

 in the United States. Its hind toe does not reach the ground where 

 it is hard ; but in deep mud it may make an impression. 



O. jpalmatus. Four toed, and all the toes directed forward. 

 The fourth toe is very short, proceeding from the inner part of the 

 foot. The heel is broad, and the toes proceed from it somewhat in 

 pairs ; that is, the two inner and the two outer ones are closer to- 

 gether, and radiate less, than the two middle ones. Toes very slen- 

 der: foot from two and a half to three inches long. Length of the 

 step, in the only specimen where it could be measured, eight inches. 



This is a remarkable species, and as I discovered it only on my 

 last visit to the Horse Race, I do not feel certain that I may not 

 have mistaken its characters ; yet the specimens in my possession 

 are very distinct. One in particular contains two tracks, and as natu- 

 ralists may probably doubt whether they were made by a bird, I have 

 given in Fig, 15, as accurate a sketch of them as possible, and of 

 the natural size, although the distance between them, which on the 

 stone is eight inches, is much diminished on the drawing. The toes 

 in one of the tracks are turned slightly to the left, and on the other 



