CONTRIBUTIONS TO ZOOLOGICAL PATHOLOGY. 
33 
clear: that he believed it to be distinct disease is also equally 
certain. In the chapter on Shortness of Breath, which he states 
is called by the old writers orthopnoea, having given what he con- 
siders to be the causes ol‘ the disease, he adds, “ which, so long as 
there is nothing broken, maye in the beginning be easilye holpen.” 
Again, in the chapter on the Pursicke, called vulsus, he says, 
“ This is a shortnesse of breath ; and the horse that is so diseased, 
I thinke, differeth not much Irom him that, hath broken lungs.” 
But enough of this. 1 must leave your readers to contrast the 
opinions expressed in 1566 with the opinions of others in 1846. 
1 trust I have shewn enough to recommend them to the favourable 
consideration of the profession, and to draw from them their opinions 
on the subject. 
I remain, Gentlemen, & c. 
Newcastle, Dec. 12. 
CONTRIBUTIONS TO ZOOLOGICAL PATHOLOGY. 
By JAMES Mercer, M.D. , Fellow of the Royal College of 
Surgeons, and Lecturer on Anatomy, fyc., Edinburgh. 
PART X. — On Entozoal, or Worm Aneurism. 
[Continued from vol. xviii, page 281.] 
The occurrence of aneurismal dilatations in the horse is consi- 
dered to be a rare circumstance by the generality of veterinarians; 
“ so rare, indeed,” says Mr. Percivall, “ that it never has, as 1 
know of, become an object of veterinary practice*.” This, indeed, 
is perfectly true of aneurisms of the larger arterial branches of the 
extremities, or in the other parts of the body without the large 
cavities, and that are deemed within the reach of surgical interfe- 
rence ; but that similar pathological conditions do take place in 
the vessels within the cavities of the trunk very frequently, and 
are productive of the most fatal consequences, is a matter which 
the light of comparative anatomical investigation is placing beyond 
the shadow of a doubt — nay, is proving to be a frequent occurrence. 
It would appear that the annals of British veterinary medicine 
afford but slight information on the pathology of the bloodvessels ; 
and in this respect our continental brethren considerably exceed us. 
* Ilippopathology, vol. ii, p. 168. 
F 
VOL. XIX. 
