144 French National Institute. 



»)ore exact tahles have been obtained for the two planet! j 

 so that the greatest error does nut at present exceed 13 de- 

 grees, and It even rises to (his Cjoantitv on one occasion only, 

 partly owing no doubt t<^ an errtn in the observation. The 

 utihty of this laboui has been extended to the ecliptic tables 

 of the satcilnes ot Jupiter, entirely rcrompused by M. De- 

 lanibre, and which v\iii soon be pubhshed. 



Zoology. — Of all the phaenoniena peculiar to certain 

 aninjals, there are few so singular and so apparently con- 

 trary to the laws of animal oecononiv a? the leihargic sleep 

 to which several vivpiarous quadrupeds are subject during 

 winter, l^iie lethargy of replilt.> and of insects during the 

 same season astonishes us n:uch less, because we are less 

 dii-posed to compare these beings with ourselves; and be- 

 cause in this stale they lose a smaller number of their ha- 

 bitual properties. 



In the lethargic mammiferae, not only does an absolute 

 state of rest take place, a complete abstinence and an insen- 

 sibility to such a degree that we may sometimes burn or tear 

 them in pieces without iheir perceiving it, but their respi- 

 ration and circulation also gradually diminish, and they lose 

 the greatest part of their animal heat, one of the most marked 

 characters of their class; in a word, their life seems totally 

 arrested j all the springs which retain or set in motion 

 the elements of organisation seem to hav6 lost their activity, 

 and yet life still remains, nay, may be prolonged by that 

 lethargy beyond its natural limits: neither death nor decom- 

 position has taken place ; and unless the cold or other acces- 

 saries of the lethargic state has ceased, the animal awakes 

 and resumes its usual functions. 



When the Class proposed, in 1799, that naturalists should 

 consider in detail the circumstances which produce, ac- 

 company, and put an end to the lethargic state, it was not 

 expected that a complete solution of the point would be ob- 

 tained, but merely that the attention of naturalists, when 

 directed to so great an object, might throw some light on it. 



The most important memoirs on this subject have ap- 

 peared in Spallanzani's posthumous Treatise on Respiration, 

 published in 1803, and in ISO/ by his friend M. Sennebier. 

 M. Mangali, ^he pupil and successor of Spallanzani, pub- 

 lished some experiments at Pavia, on the same subject*, 

 and Mr. Carlisle, in the Philosophical Transactions for 1803, 

 lias thrown much light on the question, although we are 

 not yet perhaps able to solve th'.' question. 



• See Philosopbicul Magazine, vol. ixi. p. 245. 



Messrs. 



