62 DISEASE IN WILD MAMMALS AND BIRDS 
Struthiones present the highest percentages of cardiac 
lesions, but the total specimens examined are so few that 
these figures may well be misleading. (See Tables 1 
and 2.) If, however, figures mean anything in such small 
groups, these are the animals which have the greatest 
cardiac vulnerability. They have little in common in 
regard to zoological relationships and habits ; four of the 
seven orders are rather slothful and three are active. It 
is much better to limit our observations to those orders 
from which sufficient examples have been subjected to 
autopsy and upon which we have some standards for 
comparison in the heart-body weight ratio. It so happens 
that in the above seven orders I was unable to obtain any 
reliable figures of heart weight. Table 3 is a combination 
of data from Tables 1 and 2 for the principal orders 
from which we have enough material (at least one hun- 
dred autopsies) and for which it is possible to obtain as 
comparative standards figures indicating the weight of 
the normal heart in kilograms of body weight; 
Table 4 gives these ratios for normal hearts. The 
information about the weights was obtained from 
some of our own figures and the references given in 
the footnote. (6) There are no extensive data 
upon weights and measures in exact terms, such as 
body weight, so that we are Hmited to the numbers 
quoted in parentheses besides the orders in the table. 
The ratios might be modified slightly by a greater 
number of examples, but they show certain things by 
comparison of the classes ; in a rough manner the heart 
ratios correspond to the pathology. 
(6) dal Piaz: Papers from the Department of Anatomy, University of 
California, 1912. Bergmann: Dissertation, Munich, 1884. Loer: Arch. f. 
die gesamte Physiologie, 1911, V. 140-293. Grober: Arch. f. die gesamte 
Physiologie, 1908, V. 125-507. Grober: Deutsch Archiv f. Klin. Med., 1907, 
V. 91, 502. Welcher and Brandt: Arch, fiir Anthropologic, 1903, V. 28. 
Vierordt: Tabellen, 1906. Parrot: Zoologischer Jahresbericht, 1893. 
Hasenfeld and Romberg: Arch. f. Exp. Path, und Pharmacol., 1897, V. 
39-333. Joseph: Jour. Exp. Med., 1908, V. 10-521. 
