Geographical Distribution of Insects. Ill 



to one species, analogy authorizes us to infer that the same 

 thing holds with many others, even in cases where it is abso- 

 lutely impossible to explain their distribution. This is, in 

 some degree, a consequence of the creation of species on ma- 

 ny points of the globe at once ; for, if nature thus create dif- 

 ferent types at many points, why may she not have repeated 

 in one place, a type which had been already produced in an- 

 other ? A final consideration may be derived from plants, in 

 regard to many of which botanists acknowledge a multiplied 

 origin ; and, in the present case, inferences regarding the 

 animal may be legitimately drawn from the vegetable king- 

 dom. 



(To be continued. ) 



Observations concerning the Milk of Cows, labouring under an 

 Epidemic Disorder, called Cocote, together with general 

 considerations concerning such matters as mag injuriously 

 affect the Animal Economy, and be discovered in the diseased 

 products, or in the atmosphere or ivater. Presented to 

 the Academy of Sciences by the Chemical Section, M. 

 Chevreul, Reporter. 



During the past winter, 1838-9, the milch cows of Paris 

 and its vicinity have very extensively been visited by one of 

 those epidemics, which among our neighbours is recognised 

 under the name of epizootic, and among ourselves as a mur- 

 rain. The same species of complaint had not been witnessed 

 in Paris since the year 1810, and the attack of the current 

 year, though very general, affecting most of the cattle, was 

 not of a very aggravated nature. Though the mortality was 

 not great, it produced most marked, and often impleasant ef- 

 fects upon the milk, and thus a set of the most interesting 

 phenomena, concerning epidemics and their effects upon the 

 frame, and especially on the secretions, were brought under 

 review ; and not only as affecting the lower animals, but also 

 by an easy and natural transition, upon man himself. Dr Al. 

 Donne led the way in these investigations. In the year 1837, 

 he published a pamphlet Upon Milk, and especially upon that 



