ANNOTATIONS AND ADDITIONS. 257 



unspoilt dough. May not the newly discovered monad (Monas pro- 

 digiosa), which causes blood-like spots on mealy substances, have 

 been mingled with this fungus ? 



Ehrenberg, in .his great work on Infusoria (s. 492-496), has 

 given the most complete history of all the investigations which have 

 taken place on what is called the revivification of Rotiferse. He 

 believes that, in spite of all the means of desiccation employed, the 

 organization-fluid still remains in the apparently dead animal. He 

 contests the hypothesis of " latent life ;" death, he says, is not "life 

 latent, but the want of life." 



We have evidence of the diminution, if not of the entire disap- 

 pearance or suspension of organic functions, in the hybernation or 

 winter sleep both of warm and cold-blooded animals, in the dormice, 

 marmots, sand martins (Hirundo riparia) according to Cuvier (Regne 

 animal, 1829, t. i. p. 396), frogs, and toads. Frogs, awakened from 

 winter-sleep by warmth, can support an eight times' longer stay 

 under water without being drowned, than frogs in the breeding sea- 

 son. It would seem as if the functions of the lungs in respiration, 

 for some time after their excitability had been suspended, required a 

 less degree of activity. The circumstance of the sand-martin some- 

 times burying itself in a morass is a phenomenon which, while it 

 seems not to admit of doubt, is the more surprising, as in birds 

 respiration is so extremely energetic, that, according to Lavoisier's 

 experiments, two small sparrows, in their ordinary state, decom- 

 posed, in the same space of time, as much atmospheric air as a por- 

 poise. (Lavoisier, M&noires de Chimie, t. i. p. 119.) The winter- 

 sleep of the swallow in question (the Hirundo riparia) is not sup- 

 posed to belong to the entire species, but only to have been observed 

 in some individuals. (Milne Edwards, El&nens de Zoologie, 1834, 

 p. 543.) 



As in the cold zone, the deprivation of heat causes some animals 

 to fall into winter-sleep, so the hot, tropical countries afford an 

 analogous phenomenon, which has not been sufficiently attended to, 

 and to which I have applied the name of summer-sleep. (Relation 

 historique, t. ii. pp. 192 and 626.) Drought and continuous high 

 temperatures act like the cold of winter in diminishing excitability. 

 In Madagascar (which, with the exception of a very small portion at 



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