Suspension of Life in Batracians from Cold. 71 



tliern countries, particularly in Temi-nova, according to our illustrious 

 colleague M. Larrcy.* 



Uh, To determine, and, if possible, preserve by good coloured drawings^ 

 all the modifications which take place in the colour of the skin, parti- 

 cularly its naked parts, in the "eyes, beak, &c. at the time when the 

 change in the colour of the feathers or hairs occurs ; to examine if the 

 interior membranes, for example, the mucous membranes of the m»uth, 

 do not change their colour at the same time as the external skin. 



bth, Lastly, to determine whether any changes of colour, according to 

 the seasons, more or less marked, occur in any other instances than in 

 animals covered with feathers or hair. 



Note D. — On the Suspension of Life in Batracians from the effects of cold. 



However imperfect may be the experiments which I made on this sub- 

 ject, it maj' not be useless to give a short account of them in this place; 

 thej- will at least furnish some useful hints to the zoologists of the expe- 

 dition, if they find themselves placed, as I hope they shall, in favourable 

 circumstances for the successful study of a subject upon which I was the 

 fir^t to enter. 



These experiments were made in the winter of 1828-29 on three spe- 

 cies, the common frog, common toad, and the calamite toad. They 

 did not succeed on the former of these species, for reasons which it 

 is unnecessary to mention here, but of which it is enough to say, that 

 they are no way opposed to the success of the experiments which may 

 be attempted hereafter. In the case of the toads, including both species, 

 I established the facts which may be thus shortly stated. 



Toads may be congealed, without losing life, so far that the spaces be- 

 tween the muscles become filled with small pieces of ice, and all, or nearly 

 all, the functions suspended. Their restoration, however, is possible, 

 provided the rising of the temperature be properly graduated ; they may 

 even be completely restored and recover all their wonted agility in eight 

 or ten minutes. 



In their frozen state, the toads on which I experimented gave no signs 

 of life ; their body was hard, rigid, and absolutely like a piece of a frozen 

 carcass. It was impossible to make their limbs perform the least move- 

 ment ; the smallest effort would break them ; the soft parts were so 

 hardened as to be as brittle as 'bone, and when broken not a drop of 

 blood flowed. 



The toads on which I made these observations, were placed by me, in 

 the beginning of winter, in a box filled to a certain height with earth. The 

 calamites almost immediately buried themselves in the earth, the com- 

 mon toads did so only wlien the cold became intense. It was in the 

 holes thus dug by thcmselTcs that the freezing of them was effected. 



* See his Memoires de Chirurgie Militairc et Camiwgncs, torn. i. pp. ;{1 

 Hnd :i2. 



