184 AN ATTEMPT TO DESCRIBE THE ANIiMALS THAT MADE 



middle toe, 0.35 inch ; of the outer toe, outward, 0.2 inch. Track 

 shown, of the natural size, on Plate 5, fig. 2. 



Localities. — Marsh's Quarry, Montague; north part of Montague; 

 two miles south of Turner's Falls ; and Horse Race, Gill. 



Species 3. Steropezoum elegantius. (PI. V. Fig. 3.) 



Ornithoidichnites elegantior, Mass. Geol. Rep., Plate 42, fig. 30. 



Ornithichnites diversus, /3. plalydudylus, Am. Jour. Sci., Vol. 

 XXIX. p. 319. 



Nos. 74 - 76, 79, in Cabinet. 



Divarication of the lateral toes, 70° ; of the inner and middle 

 toes, 30° ; of the middle and outer toes, 40°. Length of the mid- 

 dle toe, 2 inches ; of the inner toe, 1.1 inch ; of the outer toe, 1.3 

 inch ; of the heel, 1 inch ; of the foot, 7 inches ; of the step, 5.5 

 inches to 9 inches ; of the middle toe beyond the others, 1.2 inch. 

 Distance between the tips of the lateral toes, 1.5 inch; between 

 the outer and middle toes, 1.4 inch; between the inner and mid- 

 dle toes, 1.4 inch. Width of the foot at the roots of the toes, 0.4 

 inch. Track shown, of the natural size, on Plate 5, fig. 3. 



Localities. — Montague, Marsh's Quarry; Horse Race, Gill; and 

 South Hadley. 



Remarks. — I acknowledge it to be quite possible that the tracks 

 of this species may have been made by the young of S. elegans. 

 Yet the table of ratios annexed to this group will show quite a dif- 

 ference, in some respects, between them, besides their size. 



Genus II. ARGOZOUM. 



Digitigrade, sometimes nearly plantigrade, tridigitate. Toes 

 curved ; the lateral ones mostly outwards, somewhat keel-shaped ; 

 leptodactylous ; vertebrated. 



