FuRTiii R RrsHARc ms in Diseases oi- Plants 511 



tlic science of plant patholoi;y, atul much of the fundamental 

 study whicli has made possible its evolution was the very work 

 which he performed, thou£;h under the broad titles of plant 

 physiology and plant patholot^y. Since 1893 the theory based on 

 observation and experiment that plant organs, leaf, root, stem, 

 llower, etc., are started by some chemical phenomena produced 

 by the plant's metabolism had been announced by Sachs. Sachs's 

 theory was announced for plants practically a decade before the 

 discovery of the first animal hormone, secretin, by Bayliss and 

 Starling (1902), and many years before definite experimental 

 knowledge of prant hormones was made available. "'-^ Smith 

 interested himself in the study of the fundamentals of plant life, 

 regardless of definition or name. The study of crown gall infec- 

 tion nov,' includes the investigation of hormone effects. ^^ But, for 

 our purposes, we shall employ the descriptive phraseology and 

 terminology used by Smith. 



While at Baltimore in April, 1922, Smith worked in the labora- 

 tory of Dr. Joseph Colt Bloodgood,^^ associate professor of 

 clinical surgery and associate surgeon of John Hopkins Medical 

 School and Hospital, an excellent, able man. Smith studied stained 

 slides, microscopic sections, and other detail, of cancers of male 

 and female organs, among these being the stomach, liver, and 

 intestines, and the uterus and other abdominal parts of the female. 

 One afternoon he watched Dr. Bloodgood, whom he regarded as 

 a " great teacher," demonstrate cancers to a group of students. 

 Several times he enjoyed discussions of pathology with Dr. Welch, 

 Dr. Cullen, Dr. MacCallum, and others of his faculty friends 

 there. Dr. MacCallum told Smith " he would be glad to have 

 [him] as a plant pathologist in the new pathological building. 

 He," Smith wrote in his diary, " would let me have several rooms." 



April 24 Smith found, while reading past numbers of the 

 German cancer journal, Zeitschrijt fiir Krehsjorschuug^"'' an article 



^'William Crocker, Botany of the future, Science 88(2287): 388-389, Oct. 28, 

 1938 (discusses also Boysen-Jcnsen's work on the significance of chemical substances 

 in the oat coleoptile) ; Growth of phuits, Ttceiity years' research at Boyce Thompson 

 Institute, chap. VI, Plant hormones, pp. 204 f., by P. W. Zimmerman, N. Y., Rein- 

 hold Pub. Corp., 1948. 



'"Jour. ARric. Res. 57: 21-39, 1938. 



°^ William Carpenter MacCarty, Joseph C. Bloodgood, Surgery, gynecology and 

 obstetrics 68: 965-966, May 1939. 



'*M8(i): 110-125 (with Dr. Hans Hirschfeld), 11 figs., Berlin, 1925. 



