SCIENCE 



[N. S. Vol. XLIII. No. 1121 



tions and distinctions and building up high 

 walls of separation where nature has made 

 none, all because they do not understand 

 the plasticity of living, growing things. I 

 do not mean to condemn the study of sec- 

 tions, but only to suggest that there are also 

 other ways of looking at this problem, 

 which is one of growing things. There is 

 too much reasoning in a circle on the part 

 of many of these writers, too much argu- 

 ment basing one assumption on another as- 

 sumption as if the latter were a well-estab- 

 lished and solid fact, too little clear think- 

 ing of a biological sort, too little first-hand 

 knowledge of living plants and animals, too 

 much dogmatism, too much orthodoxy, and 

 not enough experimentation. Hence the 

 pessimism and the discouragement. 



Cancer research was born in Germany 

 and has been prosecuted there more dili- 

 gently than anywhere else in the world, 

 and they have done wonders in the study of 

 its morphology, but etiologically the best 

 the Germans have been able to do has been 

 to cover the whole situation with a cloud of 

 obscurity. With a few uninfluential excep- 

 tions they have denied the parasitic nature 

 of the disease and discouraged search for 

 an organism, and in this pessimistic atti- 

 tude they have been ably seconded by their 

 English followers. These strong men, 

 chiefly morphologists, have dominated the 

 situation for a generation, but they have 

 not explained cancer and they can not ex- 

 plain it, and they must now give way. In- 

 deed, from Cohnheim to Ribbert there is 

 not one of their arguments in opposition to 

 the parasitic nature of cancer which is not 

 as full of holes as a skimmer ! 



Listen to Ribbert in his last great book:^ 



Denn wenn auch durch Mikroorganismen knotige, 



tumorahnliehe Wucherungen hervorgerufen werden 



konnen, so handelte es sich doch stets nur um die 



9 ' ' Das Karzinom des Mensehen sein Bau, sein 

 Waehstum, seine Entstehung, " Fr. Cohen, Bonn, 

 1911. 



Bildung eines entziindlieheu Granulationsgewebes, 

 das hoehstens mit Tumoreu der Bindegewebs- 

 gruppe sine gewisse Ahnlichkeit haben konnte 

 (p. 378). 



In other words, the most that parasites 

 can do is to produce a granulomatous tumor 

 superficially like a sarcoma. 



Again he says: 



Aber wenn das fremde Lebewesen die Zellen 

 bewohnt, miissen diese notwendig geschadigt 

 werden. Das folgt aus dem Begriff der Parasiten, 

 der selbstverstandlicb der Zelle nur Nachteil 

 bringen kann. Damit ist aber die den Tumor 

 characterisierende Steigerung der Wachstums- 

 fahigkeit der Zelle nieht vereinbar (p. 384). 



In other words, when a parasite occupies 

 a cell that cell must necessarily be injured. 

 It follows out the very concept of a para- 

 site that it can only bring injury to a cell, 

 and the characteristic increase of cell 

 growth in tumors is incompatible with this 

 idea. Here as usual he just misses the 

 point. 



Ribbert ends his great book, of which 

 "seine Entstehung" is its weakest part, 

 although the illustrations are also to be 

 criticized because they are all vague wash 

 drawings when they should have been exact 

 photomicrographs, as follows: 



Das Karzinom entsteht auf Grund einer dureh 

 Epithelprodukte bewirkten die Differenzierung des 

 Epithels vermindernden und sein Tiefenwachstum 

 ausliJsunden subepithelialen Entziindung. 



In other words, if I understand him, can- 

 cer is due to a subepithelial inflammation 

 induced by substances arising in the 

 epithelium, which substances cause it (or 

 which inflammation causes it) to be less 

 well difi'erentiated and to grow downward. 

 This, etiologically, is about as clear as mudT 



Wilms, also, at the end of his book,^* 

 sarcastically inquires : 



Welches Bakterium soli wohl eine Keimblatt- 

 zelle. Mesoderm- oder Mesenchymzelle producieren 

 konnen, die dann embryonale Gewebe und Or- 

 gananlagen bildet 1 



10 " Die Misehgeschwiilste, ' ' p. 275. 



