1915] Casimir Funk 349 



the animals can live in good condition. A second serious difficulty 

 is the avidity of the tumor for food and the difficulty of rendering 

 the animal itself vitamine-free before the tumor is actually inocu- 

 lated. We saw that the tissues of pigeons that died from beriberi 

 contained a certain amount of vitamine. However, it seems worth 

 while to try the diet of unpolished rice, which is a complete diet, in 

 human Cancer, especially in rapidly growing inoperable cases. 



Centanni (150) conducted experiments similar to those just 

 referred to. He used what he called an aviride diet (seeds, dry 

 fruit), in which the products of cellular activity are at a latent stage. 

 This diet had a marked inhibitory effect on adenoma in mice, a 

 slight degree of Inhibition persisting even when fresh food was 

 given. Van Alstyne and Beebe (151) have reported results of 

 experiments with non-carbohydrate diets on the growth of sarcomas 

 in rats. They found that the sarcoma grew very much less on a diet 

 of casein and lard than on a diet of casein, lard and lactose. 



The foregoing results led Benedict and Lewis (152) to investi- 

 gate tumor-growth in rats with phlorhizin glycosuria. In such 

 cases the growth of the tumor was markedly inhibited. A similar 

 but not so striking a result was also obtained with a few human 

 cases. At present a satisfactory explanation for these results is 

 not available. 



Further proof of the importance of specific food supplies for 

 the growth of tumors is afforded by the results of experiments 

 relating to transplantation of tumors into foreign species. That this 

 is impossible, as a rule may be learned from recent papers by 

 Rondoni (153) and Nassetti (154). The transplantation of tumors 

 into foreign species has been conducted successfully, thus far, by one 

 of the following three methods (A-C). 



(A) Murphy (155) was able to implant rat tumor into a chicken 

 embryo, which demonstrates either that the organism at a growing 

 stage possesses the necessary specific substance for the growth of a 

 tumor, even from a foreign species, or that resistance to tumor 

 growth is less at embryonic stages than at later ones. That both 

 factors play important roles we shall see presently. (B) Murphy 

 and Morton were able (156) to induce tumors to grow in foreign 

 species by reducing the activity of the leucocytes with X-rays. (C) 



