596 
latter is based upon an osteological series recently 
prepared by Mr. S. H. Chubb, the former is based 
on the rich phylogenie series of Hocene titan- 
otheres in the American Museum of Natural His- 
tory. The conclusion is that ontogeny closely re- 
capitulates phylogeny, that the genesis is gradual 
or continuous, that the horns arise definitely and 
determinately. In the bovine series it seems, in 
accord with the conclusions of Diirst, that the horn 
first appears as a circular thickening of the skin, 
accompanied by accelerated growth of the hair 
preparatory to the formation of the keratin of the 
horny substance, at a period considerably prior to 
any sign of the horn in the bony structure of the 
frontals. This raises the problem, which will form 
the subject of a special paper in the Annals of 
the Academy, as to what element first arises in 
connection with horn evolution, namely: (1) the 
psychic, or desire to use the horn, (2) the epi- 
dermal callous or keratin protection of the bony 
horn center, or (3) the bony or osseous horn itself. 
It would appear that the psychic tendency must 
precede the epidermal and that the latter precedes 
the osseous, but this disputed point requires fur- 
ther investigation. 
Skull Measurements in Man and the Hoofed Mam- 
mals: HENRY FAIRFIELD OSBORN. 
Comparative anatomists and zoologists have 
been slow to introduce into mammalogy systems 
of measurement by indices and ratios, which have 
proved of such universal value in anthropology. It 
is found among the hoofed mammals, from studies 
undertaken by the author with the cooperation of 
Dr. W. K. Gregory, that cephalic indices and limb 
ratios between different segments of the skeleton 
are far more significant than systems of direct 
measurement. These cephalic indices of the grad- 
ual changes of proportion between different re- 
gions of the skull have the value of specific char- 
acters and sharply distinguish members of dif- 
ferent phyla. For example in the cross between 
the horse (#. caballus) and the ass (EZ. asinus), 
it is found that the cephalic indices are trans- 
mitted as pure non-blending characters. 
Among the most significant indices are the fol- 
lowing: (1) the cephalic, which is obtained by 
dividing the total or basilar length of the skull 
by the zygomatie breadth; (2) the cranial, which 
is obtained by dividing the basilar length by the 
postorbital length of the skull; (3) the facial, 
obtained by dividing the basilar length by the pre- 
orbital length of the skull, ete. The horses show 
proopie dolichocephaly, or elongation of the face, 
SCIENCE 
[N.S. Vou. XXXV. No. 902 
and a static condition of the cranium, while the 
titanotheres, in contrast, show opisthopic dolicho- 
cephaly, or elongation of the cranium, and abbre- 
viation of the face. Like the phyletic differences 
of proportion between the horse and the ass, these 
differences are most exactly expressed by the 
method of indices. 
The application of the ratio method to the limbs 
of the hoofed mammals has again produced most 
surprising results. It is found that mammals of 
different phyla adapted either to ‘‘weight’’ or 
to ‘‘speed’’ converge respectively toward typical 
‘¢weight’’ or ‘‘speed’’ ratios, which are obtained 
by dividing the length of the lower segments, 
tibia and radius, respectively, by the upper seg- 
ments, femur and humerus, metacarpus and meta- 
tarsus, respectively. These ‘‘weight ratios’’ and 
‘¢speed ratios’? are far more significant as re- 
gards function and phyletic change than the actual 
or direct measurements. 
This subject will be fully treated in the author’s 
forthcoming monograph ‘‘The Titanotheres,’’ to 
be published by the United States Geological 
Survey. 
Whaling in the Olden Time: FREDERIC A. LUCAS. 
The speaker exhibited lantern slides illustrating 
some interesting pictures from old works on 
whaling and showing the methods practised by the 
early Japanese, European and American whalers. 
At the regular monthly meeting of the section, 
held at the American Museum of Natural History, 
February 12, 1912, Professor Bashford Dean pre- 
siding, the following paper was read: 
Some Factors of Geographical Distribution im 
South America: JOHN D. HASEMAN. 
The speaker outlined his itinerary in Central 
South America, where he had spent the years 1907— ~ 
1910 collecting fishes, ete., for the Carnegie Mu- 
seum and studying the geology, physiography and 
faunal complexes. He criticized the ‘‘static 
method’’ of studying geographic distribution as 
leading to no certain results. He outlined his 
conception of the geology and former topography 
of South America as bearing upon the problems of 
distribution and as being distinctly unfavorable to 
the ‘‘Gondwana land’’ hypothesis. He also an- 
alyzed the faunal similarities between South 
America and Africa and held that they offered no 
valid evidence for the former existence of a land 
bridge between those continents. His results are 
being published in the Annals of the Academy. 
WILLIAM K. GREGORY, 
Secretary 
