THE 
AMERICAN 
JOURNAL OF SCIENCE AND ARTS, 
[SECOND SEBIES.] 
_ Arr. L—On Cephalization, and On Megasthenes and Microsthenes 
tm Classification (being in continuation of an article on the 
Higher eicaMeag die in the Classification of Mammals); by 
JAMES D. DAN 
In the paper on the Classification of etna published by 
the writer in the last volume of this Journal (p. 65), and also in 
his earlier paper on ns hee aciege the Saey e of cephalization i is 
shown to be exhibited among animal e following ways :— 
1. By a conse of saceahons from the locomotive to the ce- 
phalic seri 
2. By the anterior of the locomotive organs participating to 
some ieee in cephalic functions. 
creased abbreviation, concentration, compactness, and 
perfection of Stet in the parts and organs of the anterior 
erie of 
4, By jnéreased a pbreviakion, ean tte and perfection of 
structure, in the posterior, or gastric and caudal, portion of the 
body: as, in the greater compactness and larger number of seg- 
ments combined in the sacrum of the higher Megasthenes than in 
that of Cetaceans, or Edentates; the less posterior elongation of 
the vertebral column and body in the higher Megasthenes than in 
ceans, Or wo the tazlless Batrachians than in the tailed species 
of the group, e 
5. By an sowed rise in the cephalic end of the nervous sys- 
tem. This rise reaches its extreme limitin Man. Birds thus 
show their superiority to Reptiles: but not to Mammals; for the 
bird-type, like the Reptilian, is relatively diminutive in life- 
Am. Jour. Sct.—Seconp Series, Vow. XXXVI, No. 106.—Juny, 1863. 
