GEOLOGY. 687 



rate prodigiously rare, are the eggs and seeds with which 

 the panspermists burden it. 



All atmospheric corpuscules penetrate with the air into 

 our respiratory organs. Hence our lungs always contain a 

 certain amount of fecula. I have even discovered micro- 

 scopic crustaceans living in those of a dead man. 



It is known that the bones of birds, instead of being filled 

 with marrow, are perfectly hollow, and that, by means of a 

 curious mechanism they communicate with the lungs and 

 assist respiration ; hence these pneumatic bones are well 

 suited for retaining the aerial corpuscules which reach their 

 cavities. A peacock bred in a chateau presented in its 

 bones abundant filaments of wool and silk tinted with the 

 most magnificent colors ; these were clearly remains of the 

 rich dresses of the noble ladies of the place, or of work ex- 

 ecuted by their delicate hands. On the contrary, in fowls 

 from the humble abode of a baker the pneumatic cavities 

 were almost solely stuffed with meal and the remains of 

 coarse clothes ; in those of a charcoal-burner they displayed 

 numerous particles of charcoal. 



In woodpeckers, which inhabit none but the most solitary 

 parts of our forests, the respiratory passages contain only 

 the remains of leaves and bark. In contradistinction to this, 

 the bones of the crows, which pass part of their lives on our 

 roofs and part in the fields, are filled with everything that 

 circulates in the different places which they frequent. We 

 find in them variously colored filaments of wool and cotton, 

 flour and smoke, which they acquire on the roofs of our 

 dwellings ; and lastly, fine vegetable particles, which they 

 inhale in the midst of the woods. 



