INTERCELLULAR STRUGGLES AND ANTICELLULAR SERUMS.

The animal organism is regarded as a state, composed of various, more or less independent elements, which have subordinated their own interests in order to accomplish functions of vital importance. But the citizens of this cellular state do not always live in perfect harmony. There is in reality a sharp struggle among the cells for the most favorable conditions of nourishment and multiplication. Sometimes the cells devour each other and enter upon more extensive intercellular hostilities, concerning which but little in reality is known. Interesting observations are being made on the fate of diverse cells of animals when introduced experimentally into the bodies of other animals either of the same or of different species, and probably some light has already been thrown upon the nature and the mechanism of intercellular struggles. Metchnikoff, in an interesting contribution to this question¹, gives the results of experiments on the absorption of spermatozoa,