DISEASES OF THE BLOOD VESSELS 79 
especial characters unless these be in the heavy furrow- 
ing and stiffness of the wall, mth opaque, elevated, 
indefinite patches, seen mostly in the descending aorta; 
once a long tough and partly brittle stretch was found in 
the carotid. 
Alectorides, with a relatively high percentage, present 
irregularly outlined fatty and finely granular patches 
in the intima of the lower aorta and abdominal vessels, 
and, in two cases, as far as the vessels of the lower 
extremities could be followed. 
The orders Columbae and Fulicariae are missing from 
the list of Aves having arterial disease, yet a reasonable 
number of autopsy records are at hand. 
SUMMAEY ON ArTEKIOSCLEKOSIS. 
Having discussed the orders separately, a review of 
the whole situation is desirable. Chronic arteritis, or as 
it is usually called arteriosclerosis, is common to very 
many zoological orders, and its principal lesions are 
comparable throughout the two classes under considera- 
tion. A statement as to its incidence would best be made 
by adopting an arbitrary number of observations as the 
desired minimum upon which to draw conclusions, and I 
shall adopt one hundred as such a figure. Accepting this 
as reasonable, a review of the table indicates that the order 
of percentage incidence is : Accipitres 6.6, Ungulata 3.5, 
Anseres 3.4, Carnivora 3.3, Striges 2.2, Psittaci 1.8, Mar- 
supialia 1.8, Galli 1.6, Primates 0.6, Passeres 0.22; the 
other orders have less than one hundred specimens each. 
There is no doubt that carnivorous birds have the highest 
incidence of chronic arterial disease. Next in order come 
three varieties with nearly equal incidence, the ungulates, 
anserine birds and carnivorous mammals. These orders 
have little in common unless it be that in nature they are 
often engaged in prolonged or strenuous effort, as in 
fight or flight. We possess no measurement of their 
vascular supply but by consultation of the table giving 
