B. P_ I. 090. Issued June 20, 1911. 



U. S. DEPARTMENT OF AGRICULTURE. 



BUREAU OF PLANT INDUSTRY— Circular No. 85. 

 B. T. GALLOWAY, Chief of Bureau. 



CROWN-GALL AND SARCOMA. 



By Eewin F. Smith, 

 Pathologist in Charge of Lahoratonj of Plant Pathology. 



INTRODUCTION. • ' 



In a recent bulletin of the Bureau of Plant Industry of the United 

 States Department of Agi'iculture ^ the writer pointed out resem- 

 blances in crown-gall of plants to malignant animal tumors and 

 especially to sarcoma. Since the publication of this bulletin further 

 .study has revealed several very interesting facts. Our observations 

 show that in method of development this disease is strikingly like 

 that of certain malignant neoplasms in man, especially those in which 

 a distinct strand of tumor tissue has been traced from the primary 

 tumor to the secondary tumor. 



There is perhaps no metastasis, in the strict sense of the tenn, but 

 so far as regards the mechanism of tumor development it is a matter 

 of minor importance whether the migrating tumor cells separate 

 themselves entirely from the parent mass or remain connected with 

 it by means of a tumor strand. The plant body favors the latter 

 method of development, whereas the rapidly circulating blood stream 

 in animals favors the former, i. e.. the dislodgment and distribution 

 of cells. The matter of chief importance is the method of action of 

 the parasite on the cells of the host. 



QUESTIONS UNSOLVED. 



In the bulletin mentioned the following subjects were either not 

 touched upon or left in an inconclusive state : 



(1) The question of the presence or absence of the bacteria in the 

 secondarj^ tumors. 



1 Bulletin 213, Bureau of Plant Industry, U. S. Dept. of Agriculture, entitled " Crown- 

 Gall of Plants : Its Cause and Remedy." The edition of this bulletin is exhausted at the 

 Department of Aj.'riculture. It may be obtained, however, from the superintendent of 

 documents. Government Printing Office, Washington, D. C. Price 40 cents. 

 100097° — Cir. 85—11 



