1885. ] On the Evolution of the Vertebrata, etc. 341 
From this I infer that two hundred to three hundred years ago 
the deer, elk and buffalo in their many wanderings across streams 
and over hills, have occasionally carried in their hoofs partly 
sprouted seeds, and dropped them on the hills where the sun- 
shine was unobstructed, and the trees thus got their footing, and 
once getting it were able to stand afterward. These are the only 
kinds of trees I have observed, but I presume a similar law gov- 
erns the distribution and self-planting of them all. 
10: 
ON THE EVOLUTION OF THE VERTEBRATA, PRO- 
GRESSIVE AND RETROGRESSIVE. 
BY E. D. COPE. 
(Continued from page 247, March number.) 
Tue REPTILIAN LiNE—CONTINUED. 
igs the first place, this line departs with lapse of time from the 
primitive and ancestral order, the Theromorpha, in two re- 
spects. First in the loss of the capitular articulation of the ribs, 
and second in the gradual elongation and final freedom of the 
suspensory bone of the lower jaw (the os quadratum). In so 
departing from the Theromorpha, it also departs from the mam- 
malian type. The ribs assume the less perfect kind of attach- 
ment which the mammals only exhibit in some of the whales, and 
the articulation of the lower jaw loses in strength, while it gains 
in extensibility, as is seen in the development of the line of the 
eels among fishes. The end of this series, the snakes, must 
therefore be said to be the result of a process of creation by 
degeneration, and their lack of scapular arch and, fore limb and 
usual lack of pelvic arch and hind limb are confirmatory evidence 
of the truth of this view of the case. 
Secondly, as regards the ossification of the anterior part of the 
brain-case. This is deficient in some of the Theromorpa, the an- 
cestral order, which resemble in this, as in many other things, 
the cotemporary Batrachia. Some of them, however (Diadecti- 
dæ), have the brain completely enclosed in front. The late orders 
mostly have the anterior walls membranous, but in the strepto- 
stylicate series at the end, the skull becomes entirely closed in 
front. In this respect then the snakes may be said to be the 
highest or most perfect order. | 
As regards the scapular arch, no order possesses as many ele- 
