SHSoOmaNIaraa fP O&O WN = 
or 
NASH oO FR OO NDF OS 
24 
. Toes thick, pachydactylous ; or thin, leptodactylous. 
. Feet winged. 
. Number of toes from two to five, inclusive. 
. Absolute and relative length of the toes. 
. Divarication of the lateral toes. 
. Angle made by the inner and middle, outer and middle toes. 
. Projection of the middle beyond the lateral toes. 
. Distance between tips of lateral toes. 
. Distance between tips of middle and inner and outer toes. 
. Position and direction of hind toe. 
. Character of claw. 
- Width of toes. 
. Number and length of phalangeal expansions. 
. Character of the heel. 
. Irregularities of under side of foot. 
. Versed sine of curvature of toes. 
. Angle of axis of foot with line of direction. 
18. 
. Length of step. 
. Size of foot. 
. Character of the integuments of the foot. 
Distance of posterior part of the foot from line of direction. 
. Coprolites. 
. Means of distinguishing bipedal from quadrupedal tracks. 
By these characters, President Hitchcock has dis- 
tinguished physiological tracks, or those made by 
animated beings, into ten groups provisionally. ‘To 
these may be added, “ organic impressions,” made 
by organized bodies; and the impressions made by 
inanimate bodies, called “ physical impressions.” 
The specimens under our hands enable us to give 
some notion of the distinctions which characterize the 
greater part of these groups. 
