1881.] Invertebrate Paleontology in the U.S. for 1880. 273 
the hogs and hippopotami, the lowest of the Artiodactyla, Now in 
progression on dry land, any preéxistent inequality in the length of 
the digits would tend to become exaggerated. Such an inequality 
exists in the Asmélypoda, the third digit being a little the longer. 
In rapid movement on hard ground the longest toe receives the 
gfeatest part of fhe impact, even if its excess of length is but lit- 
tle. The harder the ground the larger the proportion of impact 
it will receive. 
The fact that the Perissodactyla did not develop the solidungu- 
late or equine foot, until a late geological period, or in other words, 
that the orders so long retained the digital formula 4—3, would 
indicate that it did not adopt a habitat which required great speed 
as a condition of safety, so early as the Artrodactyla. ; 
be ma cana, 9% 
PROGRESS OF INVERTEBRATE PALAZONTOLOGY IN 
THE UNITED STATES FOR THE YEAR 1880. 
BY DR. C. A, WHITE. 
fade palzontological work of 1880: has been done mainly by 
the same persons whose works were noticed in the NATURAL- 
Ist’s review for 1879. None have died during the past year, and at 
least one new worker has appeared in the ranks of American 
palaontologists. With one important exception the channels for 
the publication of the results of paleontological work remains the 
Same as last year. Palaeontology has suffered a serious loss in the 
closing of the important channel of publication which was for so 
many years afforded by the Government Survey under the direction 
of Dr. Hayden. At present, therefore, no great works of well illus- 
trated invertebrate palzontology are in progress, except those of 
New York, Ohio and Wisconsin, but more especially that of the 
first-named State. : 
Dr. Charles Barrois, of Lille, France, published in the Revue 
Scientifique (Paris), for September, 1880, a review of Volume v, 
Part 11, Paleontology of New York, by Professor James Hall; and 
a translation of the same was published in the January, 188t, 
number of the American ¥ournal of Science. In that review Dr. 
Barrois gives, besides a summary of the contents of the volume, 
Some interesting discussion of the relation of the Devonian Gas- 
