MALIGNANCY 47 



where infection is negatived by the whole of the pheno- 

 mena of ovum and uterine interaction, X-ray malignancy 

 and allied phenomena point straight to the conclusion 

 that the explanation of cancer lies in the relations of epithe- 

 lium and connective tissue; that benignity is a normal 

 reaction and malignity a failure ; that irritation is only a 

 means by which the normal reactions of these tissues are 

 destroyed ; and that infections are only causes so far as they 

 excite or depress and thereby destroy the balance of tissues 

 which exercise outside control by their mechanical nature 

 and products. I have so far found no theory but the one 

 here advocated that reconciles all these phenomena, and 

 it is a fact that it enabled me to prophesy many observa- 

 tions quite unknown to me at one period of investigation. 

 Conclusions of this kind are necessarily as relevant to 

 sarcoma as to carcinoma. The immense activity of con- 

 nective tissue in youth suggests that it might at any age get 

 out of hand. Fowls seem specially liable to it. Luckily 

 they mostly die young. An aged fowl, which should be 

 liable to carcinoma, is a rare object. As a domestic 

 animal which, owing to the caprice of breeders, is in a 

 peculiarly fluent condition, it is particularly liable to loss 

 of balance. Uterine or mammary cancer is rare in bitches, 

 a fact very properly attributed to their commonly dying 

 before involution sets in. It may also be due to their 

 habits, since they are not so much exposed to sexual stimuli 

 as human beings, who only practice continence during the 

 oestrus. It is said that castrated animals are more liable 

 to malignant diseases than others. They have been thrown 

 out of normal balance by operation. The peculiar deadli- 

 ness of sarcoma seems natural enough if we remember thai 

 it is to connective tissue that all repair is due. It is a 

 case of " quis custodiet ? " when the guardian tissue 



