I90 ANCIENT, EDENTATES CHAP. 
to the Anteaters of the New World are chiefly adaptive and have 
nothing to do with real affinity, being merely an expression of a 
similar mode of life, it is curious to note that here and there we 
do find certain resemblances which do not seem to be susceptible 
of the latter explanation. The Jugal bone, absent in Janis, is 
small in Myrmecophaga ; the clavicle is absent and again small or 
rudimentary in the Anteaters; it is large in other Edentates. 
Fie. 109.—Manis. Janis gigantea. x 4)5. 
The third trochanter is absent, as in IMJyrmecophaga (and the 
Sloths). There are many scales on the body; in Myrmecophaga 
there are traces of these structures on the tail, as also in 
Tamandua. In the features mentioned, the Myrmecophagidae 
differ from either or from both of the two other American 
families (i.e. Dasypodidae, Bradypodidae) and agree with Janis. 
The facts are not a httle remarkable. 
Order III. GANODONTA.' 
Allied to the Edentata, and apparently representing the 
ancestral forms from which they, at any rate the Xenarthra 
were derived, is the order of the Ganodonta. Of this order a 
number of genera are now known, which can be ranged in a 
series which more and more approaches the Edentata as we pass 
from the older to the newer forms. This interesting and transi- 
tional series will be made manifest by a description of the 
characters of the various genera taken in their proper chrono- 
1 See Wortman, ‘‘The Ganodonta and their Relationship to the Edentata,” 
Bull. Am. Mus. Nat. Hist. ix. 1897, p. 59. 
