OF FOSSIL FOOTMARKS. 255 



Plate 37, figure 20 of my Report ; which ought, perhaps, to have 

 been re-drawn from a more perfect specimen for this paper. But 

 I am anxious to make my sketches as few as possible. 



OrnitJioidichnitcs tuhcrosus. Toes tliree in front, straight, spread- 

 ing forty degrees : tuberous swellings remarkably distinct and broad : 

 two on the inner or shorter toe ; three on the middle toe, and four 

 on the outer toe. Claws distinct, acuminate, from an inch to an 

 inch and a half long. Middle toe extending nearly three inches 

 further forward than the lateral ones. Length of the middle toe, 

 (reckoning from the posterior extremity of the tuberous swellings to 

 the extremity of the claw,) five to six inches. Length of the foot, 

 seven to nine inches. Length of the step, twenty-five to thirty- 

 three inches. 



This species occurs in the greatest abundance at Turner's 

 Falls and the south part of Northampton ; but it is found at al- 

 most every locality of footmarks in the valley of the Connecticut, 

 and recently, (December, 1842,) it has been discovered by Wil- 

 liam C. Rcdfield Esq. in the red sandstone of New Jersey, at 

 Pompton, in connection with the impressions of rain drops. This 

 is the first time a fossil footmark has been found in this country out 

 of the valley of Connecticut river. The fact is, therefore, of great 

 interest. Although the middle toe of the specimen was broken off, 

 yet the tubercular swellings on the lateral toes, and their claws, 

 were remarkably distinct, and could not have been mistaken by 

 one so familiar with footmarks as Mr. Redfield. 



The variety of O. tuberosus of my Report which has now been 

 described, diflfers so much from the other varieties given in Plate 

 37, figm-e 21, and Plate 88, figure 22, that I hesitate not 

 to describe the latter as a distinct species. They differ from 

 the O. tuberosus, chiefly in being in every respect more slender 

 and delicate ; a distinction which it is not easy to make in a de- 

 scription, though obvious to inspection. This new species, which 

 I found upon the above figures of my Report, I propose to de- 

 nominate O. Sillimani, as a testimony of my respect for the char- 

 acter and the valuable and Ions; continued labors of Professor 

 Silliman in the cause of science. Its description is as follows : 



