372 
RUPTURE OF THE AORTA IN A HORSE. 
carnivora ; that is, by absorption of the fang and throwing off of 
the body at once, as the animal is still able, by the lips and other 
incisors, to gather in the grass ; and, therefore, an interruption of 
the complete row is of less consequence. 
It must be viewed as a wise provision, that the replacement of 
organs so important to the growth and well-doing of the animal 
should take place at these particular seasons of the year. It is a 
fact well known in breeding districts, that a colt always gets thin- 
ner during the shedding of the molar teeth, and does best at grass : 
and the popular belief is in accordance with the physiological fact, 
both as to the period at which the change is made, and also the 
best mode of contributing to the well-doing of the animal. 
In the country in which the horse is believed to have been ori- 
ginally placed, the rainy season generally lasts from June to Sep- 
tember, and in an arid country the first falling of rain causes 
the growth of plants to be very rapid and succulent : this enables 
the animal to easily masticate the food necessary for its growth 
and well-doing ; and as the food and the teeth become firmer con- 
currently, it also allows of a supply of spare nutriment, in the 
shape of fat, to be laid by for a more rigorous season. The same 
result will be apparent at the cessation of a rainy season in the 
same countries ; for the heat which then predominates will have 
the effect, upon a soil saturated with moisture, of increasing the 
succulent growth of plants suited to an herbivorous animal. And 
thus I think it will appear that these important changes, taking 
place at these precise periods, must be viewed as a wise ordination 
of Providence ; for though the habits of an animal may be slightly 
modified by locality or other changes in the position in which 
it may be placed, yet not any change has yet been able to be 
traced either in internal organization, changes during growth, or 
the peculiarities stamped upon its reproduction : they still remain 
the same as when first created. 
June 10, 1845. 
RUPTURE OF THE AORTA IN A HORSE. 
By W. A. Cartwright, M.R.C.V.S., Whitchurch, Salop. 
On the 3d April, 1845, I was sent for by Edward Eyton, Esq., 
of Marbury Hayes, to examine a half-bred horse that had died sud- 
denly the previous night 
The horse belonged to G. Harper, Esq., of this town, and had 
been lent to Mr. Eyton to do a little work. He was about 15 
