Harley^ on Cutaneous Respiration. 
157 
complete suspension of the functions of the skin by means of 
a coating of varnish_, gave rise to a state which he has 
described by the name of cutaneous asphyxia. In his expe- 
riments he observed that this condition was accompanied by 
an imperfect arterialization of the bloody upon which rapidly 
followed a marked decrease of the animal heat. This showed 
that the application of the varnish to the skin had not only 
prevented the insensible perspiration^ but also the exhalation 
of carbonic acid and the absorption of oxygen. Had the 
perspiration alone been interrupted, the temperature of the 
animaFs body would have increased, since it is to the evapo- 
ration of the sweat that the reduction of the animal heat is 
principally due. The constant evolution of heat from the 
cutaneous surface is replaced by the warmth developed during 
the combustion of the oxygen introduced through the skin 
and lungs, with the carbon and hydrogen of the tissues. 
The frog^s skin is so perfect a respiratory organ, that in the 
absence of the lungs, it can carry on the dilFusion of gases 
efficiently enough to support the life of the animal during 
several hours. Professor Moleschott has recently commu- 
nicated to the French Academy some interesting experiments 
upon the efPect of light upon the cutaneous respiration of the 
frog, showing that the function is much more rapidly per- 
formed in the sun's rays than during the absence of light. 
In the daytime more oxygen was absorbed, and more car- 
bonic acid exhaled by the skins of the animals than during 
the night. From the peculiar organization and mode of 
life of this animal, as well as from the wide distribution and 
singular construction of the organs which it has been the 
purpose of this communication to describe, it appears not 
improbable that the follicles in the skin are more employed 
in the function of respiration than of perspiration; and I 
think we may therefore regard them rather as animal stomates 
than sudoriferous glands. 
