SCIENCE 



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



conceivably, give rise to the same chemical 

 and physical stimulus. 



Wilms in his book on "Die Mischge- 

 schwiilste" (Heft 3, Leipzig, 1902, p. 242), 

 if I understand him correctly, considers 

 the blastomous portions of embryoid tu- 

 mors to be of a secondary nature, as do 

 other writers, but in this assumption they 

 are probably wrong. 



To the statements of these authors claim- 

 ing the cancerous element to be secondary, 

 may be replied: The same could be said of 

 the shoot-producing tumors on Pelargonium 

 and on tobacco did we not know experi- 

 mentally that it is actually the infected tu- 

 mor tissue which is the earlier and which 

 has stimulated the normal tissues to de- 

 velop. Moreover, which tissue is the earlier 

 is a matter that can not be determined by 

 mere observation of sections (Betrachtung 

 des Wachstums — Wilms), but one to be 

 worked out experimentally. 



To condense results, I may say that dur- 

 ing the past winter I have discovered that 

 when the crown-gall organism {Bacterium 

 tumefaciens) is introduced into the vicinity 

 of dormant buds on growing plants atypical 

 teratoid tumors are produced quite reg- 

 ularly. I have obtained these in Pelargo- 

 nium, tobacco (2 species), tomato. Citrus, 

 Bicinus, etc. Apparently what happens is 

 this: The bud anlage are torn into frag- 

 ments by the rapidly growing tumor and 

 these fragments are variously distributed 

 and oriented in the tumor where under the 

 stimulus of the parasite they grow into 

 abortive organs variously fused and 

 oriented, some on the surface of the tumor, 

 others in its depths. Surface fasciation 

 occurs. Also in the depths of the tumors 

 fragments of organs occur, lined by mem- 

 branes bearing trichomes (hairs) and lying 

 upside down and variously oriented and 

 combined. The flower shoots and leaf 

 shoots on the surface of such tumors vary 



greatly in number and in size, often they 

 are the merest abortions and in that ease 

 there may be a hundred or more of them 

 (leafy shoots or flower shoots) on a single 

 tumor, especially on the Pelargonium. 

 Even the largest and best developed sur- 

 face shoots if they arise out of the tumor 

 tissue and not from its vicinity are feebly 

 vascularized and become yellow and dry up 

 within a few months and often before the 

 tumor itself decays. Such shoots never 

 come to maturity. Immature fragments of 

 ovaries and of anthers also occur on the 

 surface and in the depths of such tumors. 



These teratomas when produced in leaf 

 axils on the castor oil plant reach a large 

 size and perish quickly, i. e., often within 

 2 months. Frequently in this plant the 

 neighboring glands on the base of the leaf 

 stalk are also invaded (within 2 or 3 weeks) 

 and greatly enlarged. This is one of the 

 striking results on Ricinus to which I would' 

 call special attention, since it is very sug- 

 gestive of what often occurs in cancer in 

 man, that is, of the malignant enlargement 

 of lymph glands in the vicinity of a cancer. 

 Following inoculations on the middle part 

 of the leaf-blade of Bicinus I have also traced 

 a parenchymatic tumor-strand down the 

 petiole a distance of 11 cm. This was nearly 

 circular in cross-section, large enough to be 

 visible to the naked eye and composed of 

 parenchyma cells. Corresponding to this 

 were swellings on the surface of the petiole 

 and bulging into the petiole cavity, but no 

 ruptured tumors. No teratoids were 

 formed on the Ricinus leaves. 



Daughter tumors are produced freely on 

 tobacco if the inoculations are made early 

 enough, and these often reproduce all the 

 teratoid elements of the primary tumor, 

 e. g., daughter tumors 10 inches away from 

 the primary tumor may bear leafy shoots. 

 These secondary tumors, which have been 

 seen both in stems and in leaves, are con- 



