300 A Pathogenic Schizophyte of the Hog. [April, 



water. If the rain is a light one, the Schizophytes are apt to 

 remain where the rain-drops deposit them, till evaporation once 

 more carries them up into the air, but if the rain is very heavy or 

 pouring, and temporarily flooding the ground, the Schizophytes, 

 it seems, are washed away, for it can be observed that after light 

 rains the spreading of the disease is accelerated, while immediate- 

 ly after each heavy or pouring rain a temporary diminution, 

 often almost amounting to a cessation, can be noticed. 



6. As already mentioned, it is an established fact that external 

 wounds, especially such as are caused by ringing, castration, cut- 

 ting of tails, and slitting of ears, external sores, scratches, and 

 even abrasions, attract and absorb the infectious principle, and 

 that the disease is also communicated, though not as readily as 

 through wounds, etc., if the infectious principle is introduced 

 with food or water for drinking into the digestive canal, while I 

 have never yet been able to observe, or to obtain any evidence, 

 that the infectious principle does enter, or can enter, the animal 

 organism through a healthy skin, or through the respiratory organs, 

 if the mucous membranes are in a perfectly healthy condition, or 

 free from any sores, wounds, or abrasions. It has even been re- 

 peatedly observed that an animal whose skin and mucous mem- 

 branes are whole and healthy, will not contract the disease, and is 

 perfectly safe, if separated only by a fence, a board fence, or a 

 board partition from diseased animals, provided, of course, an in- 

 troduction of the infectious principle through the alimentary canal 

 is prevented. All this shows that the infectious principle must be 

 something that is very minute, but corporeal, and endowed with 

 life and power of propagation, and not an invisible poisonous 

 fluidum, for the latter, most assuredly, if dissolved in air, would 

 find its way through the lungs, and, very likely also through the 

 healthy skin into the animal organism. 



7. If the morbid process is taken into consideration — for par- 

 ticulars I have to refer to my published reports, as going into de- 

 tails would consume too much time — it also becomes evident that 

 something corporeal and endowed with life and power of propaga- 

 tion must constitute the cause of the disease. The morbid pro- 

 cess in all parts and organs, in which it may develop, essentially 

 the same, is best studied in the skin, subcutaneous tissues, and 

 particularly in the lungs. At first the finer capillaries become ob- 

 structed, as a consequence, more or less blood serum transudes 



