1911-12.] Body Temperature of Diving and Swimming Birds. 33 
According to Roger * the sex influence shows itself even before the age of 
puberty. He found in ten boys a mean rectal temperature of 37°*107, while 
in fourteen girls of the same age (before puberty) the figure was 3 I 7°191, 
giving a difference of scarcely one-tenth of a degree centigrade. Ogle *f* states 
that in the adult the difference in the mean temperature does not exceed half 
a degree Fahrenheit (about 0 o, 3 C.), the woman having the higher figure. 
In the case of the domestic fowl, Davy J found that for three cocks the 
mean temperature was 42°’4 C. and for three hens 42°’l C. Here again his 
conclusions are probably erroneous, for the reason that they are based on 
the examination of an insufficient number of individuals. As already 
mentioned, Martins § found that in the domestic duck the male had a mean 
rectal temperature of 41°‘91 and the female of 42°’27. He obtained his 
figures from fifty drakes and sixty ducks. In this relation it may be 
mentioned that the writer, in the course of another investigation, has made 
hundreds of observations on the rectal temperature of the domestic fowl,, 
and from these it is shown that the temperature of the hen is slightly 
higher than that of the rooster. Similarly, in the case of wild birds belong- 
ing to orders other than those under consideration in the present paper, 
Simpson and Galbraith || found that the mean temperature of the female 
was higher than that of the male in all the species examined whose sex had 
been determined. 
Body Temperature in Relation to Position in the Zoological Scale . — In 
the conclusion to an article on “ The Temperatures of Reptiles, Monotremes, 
and Marsupials ” Sutherland f says : “ It is clear, therefore, that there are 
grades of temperature, and that the mammals which are classed lowest on 
anatomical grounds are not only of the lowest temperature but also of the 
greatest range. . . . Similar, though much less complete, connecting links 
may be seen in the case of birds. The lowest of birds are the Ratitse or 
Cursores, and these appear to have the lowest temperature. ...” Observa- 
tions on the temperature of the emu were made for him in the Melbourne 
Zoological Gardens, and “ these are the lowest records of bird temperatures 
of which I know. They averaged 39° *5 C., while all the birds above the 
Ratitse are invariably over 40° C.” He goes on to show that if the birds 
were arranged in the order of their body temperatures the series would 
probably run parallel with the zoological series. 
* Roger, Richet’s Didionnaire de Physiologie , t. 3, p. 96. 
+ Ogle, Wunderlich’s Medical Thermometry , p. 99. 
I Davy, loc. cit. 
§ Martins, loc. cit. 
|| Simpson and Galbraith, Jour, of Physiol., vol. xxxiii., 1905, p. 225. 
% Sutherland, Proc. Roy. Soc. Victoria , 1896, p. 57. 
VOL. XXXII. 
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