DR. MARSHALL HALL ON HYBERNATION. 
349 
tage dans certaines parties du meme animal. Mais.ce qui est prouve jusqu’a 
l’evidence, c’est que ce principe a bien plus de tenacite dans les chairs de Tani- 
mal tue pendant l’etat de lethargie, que dans celles de l’animal tue pendant 
1’etat de veille.” 
This author does not appear to have had any apprehension of the extreme 
importance of this extraordinary change in the irritability, but merely states 
it as a fact. Its due value can only be known by observing the dependence of 
the functions of life on that law of the inverse condition of the respiration and 
of the irritability, of which so much has already been said. In the hybernating 
animal the respiration is nearly suspended ; had not the irritability become 
proportionately augmented, the actions of life must have ceased ! 
3. Of the Sensibility. 
All the writers upon the subject of hybernation agree in stating that the 
sensibility is greatly impaired ; and it is impossible to commit a greater mis- 
take. 
The slightest touch applied to one of the spines of the hedgehog immediately 
rouses it to draw that deep inspiration of which I have spoken. The merest 
shake induces a few respirations in the bat. The least disturbance, in fact, is 
felt, as is obvious from its effect in inducing motion in the animal. 
It is from the misconception on this point that the error has arisen, that the 
respiration is not absolutely suspended in hybernation. This function has been 
so readily excited, through the medium of an unimpaired sensibility, that the 
event has been considered as appertaining to the state of hybernation. 
In fact, the sensibility is in nearly the same condition in hybernation as in 
ordinary sleep. 
It must appear extraordinary that with an unimpaired sensibility there can 
co-exist a suspended respiration. Why is not this suspension of respiration 
painful in the hybernating, as in other animals ? And why is not the animal 
roused, by this pain, from its slumbers, if its sensibility be only slightly im- 
paired ? 
But we should first ask, what are the precise seat and source of that pain 
which is felt during the suspension of respiration ? These are, I think, demon- 
strably, the heart, and an impeded circulation through this organ. If, there- 
2 z 
MDCCCXXXII. 
