The Life of the Fly 



body of the nurseling by a process akin to that 

 known In physics as endosmosis.^ What should 

 we say to a method of being suckled by the 

 mere application of the mouth to a teatless 

 breast? What we see here may be compared 

 with that : without any outlet, the milk of the 

 Challcodoma-grub passes Into the stomach of 

 the Anthrax' larva. 



Is It really an Instance of endosmosis? 

 Might It not rather be atmospheric pressure 

 that stimulates the flow of nourishing fluids 

 and distils them into the Anthrax' cup-shaped 

 mouth, working, In order to create a vacuum, 

 almost like the suckers of the Cuttlefish? AlV 

 this Is possible, but I shall refrain from de- 

 ciding, preferring to assign a large share to 

 the unknown in this extraordinary method of 

 nutrition. It ought, I think, to provide physi- 

 ologists with a field of research In which new 

 views on the hydrodynamics of live fluids 

 might well be gleaned; and this field trenches 

 upon others that would also yield rich har- 

 vests. The brief span of my days compels me 

 to set the problem without seeking to solve It. 



And the second problem Is this : the Chali- 



^The transmission of a fluid inward through a porous 

 partition which separates it from any fluid of a different 

 density. — Translator's Note. 



40 



