Recent Agricultural Puhlicaiions. 413 
!The publishers have produced the English edition in a most 
attractive style — paper, letter-press, and illustrations are all good 
and pleasing. It is true that the translation is the work of an 
American authority, but English readers will none the less give it 
a cordial welcome on that account. Dr. Harger has, indeed, credi- 
tably acquitted himself of what must have been a very difficult task, 
and all who have occasion to consult the volume will readily agree 
with the translator that it contains valuable information for the 
practitioner, the student, the horseman, and the breeder. 
GUIDES TO THE AGE OF LIVESTOCK.* 
As might be expected from the relative importance of the subject, 
considerably more than half of this work is devoted to the dentition 
of the horse. In the Society’s pamphlet, “ Dentition as indicative 
of the Age of Farm Animals,” Professor Brown has dealt in a 
popular way with the subjects which are more fully treated in the 
volume under notice, which comes from the pen of an American 
veterinarian. After an instructive chapter on the form, structure, 
and general characters of teeth, the author proceeds to divide the 
life of the horse into five periods. Of these, the first extends from 
the eruption of the incisors of the first (or milk) dentition to the age 
of ten months. The second period, ending at two years, is marked 
by the levelling, progressive use, and falling out of the incisors of 
the first dentition. The third period extends till the age of the 
animal is five years off, and is characterised by the eruption of 
the permanent or adult teeth. The fourth period, during which the 
levelling of the permanent incisors is in progress, ends when the 
horse is eight years old. After this time, which we are told is 
commonly known as “ past mark of mouth,” the chief indications of 
age are afforded in the wearing away of the crowns of the teeth, the 
fifth period comprising the remainder of life after the eighth year 
has been completed. 
One of the most interesting sections of the book is that dealing 
with irregularities in the dental .system of horses. These are classed 
as (1) increase or diminution in the normal number of teeth, (2) 
unusual shape of incisors, (3) uiiion of two incisors, (4) fissure of the 
dental cup, (5) abnormal depth or size of the dental cup, (6) exces- 
sive length or size of one of the jaws, (7) excess or fault of use, (8) 
marks produced by cribbing, (9) fraudulent alterations, — removal of 
the milk-teeth, bishoping, tiling the corners. 
Horses have been known with double rows of incisor teeth, — the 
author’s phrase, “incisive teeth,” is not commendable. Super- 
numerary molars have only been found in the upper jaw. Diminu- 
tion in the number of incisors is less frequent than augmentation, 
* Af/e of the Doviestic Animals, heimj a complete Treatise on the Dentition 
of the Horse, Ox, Sheep, Hog, and Dog, and on the various other Means of de- 
termining the Age of these Animals. By Rush Shippen Huidbkopep., M.D. 
Pages viii-t-217, with 194 illustrations. Philadelphia and London: F. A. 
Davis. 1891. 
VOL. III. T. S. — 10 E E 
