miscellaneous: experimental teratosis 581 



slowly and developing several small, green leaves, which may be 

 of the ordinary shape or may be variously malformed or grown 

 together. They do not separate naturally from the parent 

 plant to root freely, like bulblets, neither are they to be re- 

 garded as branches, except in so far as they subsequently become 

 connected with the vascular system of the mother plant, but 

 under very exceptionally favorable conditions, as is well known, 

 such adventive shoots can be grown into large plants, i.e., 

 when separated artificially from the parent plant, rooted with 

 great care in sand, and potted in good soil. Unlike Bryophyllum 

 no roots develop from these proliferations as long as they 

 remain attached to the plant, nor do they root freely in sand. In 

 other words, the shoots are of no use to the plant and their 

 development cannot be explained teleologically. 



9. The extent of their development on the plant depends 

 very largely on the nutrition of the particular organ from which 

 they have sprung. If the leaf, for example, remains small they 

 are correspondingly dwarfed, many being scarcely more than 

 slightly raised green places (pimples) on the surface of the leaf. 

 They are better developed on large, well-nourished, actively 

 growing leaves and on such leaves a few shoots, especially 

 those over midribs where the water supply is most abundant, 

 may develop several leaves with blades an inch or more in 

 length. I have grown one such laminar shoot (Fig. 428C) 

 into a plant 12 inches high, all its nourishment coming through 

 the rooted petiole of the mother leaf, the blade of which soon 

 perished. It is, however, a crooked stunted plant. 



10. In earliest stages of development these proliferous shoots 

 are very superficial. Unlike the normal axillary buds they have 



nodes in similar buds which specially responded to the root-stimulus, as described 

 in the text and as shown on the following plates. Nat. size. 



B. Same as A but with the outermost 2 stipules removed to show the larger 

 of the three folded leaves. X 2. 



C. Plant which developed from an adventive shoot on a leaf blade. (1) 

 Rooted petiole. (2) Blade of the mother leaf which soon shriveled. Photo- 

 graphed July 15, 1918. 



D. Portion of upper main axis of No. 1, first series, enlarged to show the lenticels 

 (spindle-shaped white markings) and the glands (numerous white specks) from 

 the base of which most of the adventive shoots arise. X 4. 



