(No) 
Or 
GROUP FIRST —STRUTHIONES. 
The ostrich-tracks present a numerous natural 
and most remarkable group; remarkable from the 
great size of some species, — all of them tridactylous 
and pachydactylous. The ostrich of the Old World 
has only two toes, but this family exists in South 
America at the present time under the name of Rhea 
Americana; and tracks of an animal, probably of the 
same family, are found in the numerous impressions 
near Connecticut River, —all of them having three 
toes in front, and the rudiment of a fourth behind. 
This group contains a number of genera. The 
First Genus, denominated Brontozoum, presents the 
tracks of a most extraordimary bird. These tracks 
appear less questionable since the discovery in Mada- 
gascar of the eggs of the Epyornis. 
The tracks of the largest species, the Brontozoum 
GIGANTEUM, are four times the magnitude of those 
made by the existing ostrich of Africa. They are 
very numerous, and congregated together. The foot 
of the Brontozoum Giganteum, including the inferior 
extremity of the tarso-metatarsal bone, which makes 
a part of the foot, measures in our specimen twenty 
inches ; in the Mastodon Giganteus. the foot measures 
4 
