Francis E. Lloyd —132— Carnivorous Plants 



regarding this a repetition of phylogeny. Winkler (1903) observed the 

 lack of polarity in the occurrence of leaf buds in D. capensis, as in 

 Torenia and Begonia, and further for the first time showed clearly that 

 the buds arise not from retained embryonal tissue, but by redifferentia- 

 tion of the leaf tissues. 



Exact studies of the mode of origin of the adventitious buds of the 

 leaf surface have been made by Behre (1929) and by Vickery (1933), 

 the latter author independently confirming the former in all essentials. 

 Such leaf buds arise on the blade always from the bases of tentacles, 

 usually on the adaxial surface, but occasionally laterally or even adax- 

 ially (Behre). They are often visible in a few days if during that time 

 the leaf has been separated from the plant and kept under moist con- 

 ditions. The cells involved have in all cases arrived at maturity, and 

 there is no sign of the persistence of embryonic tissue. The cells there- 

 fore undergo a true rejuvenation passing from an adult, vacuolated 

 condition into one of high protoplasmic content with accompanying 

 changes in the nucleus. They then undergo cell division previous to 

 growth, the earliest divisions, in general, being anticlinal, followed by 

 perichnal {16 — 7, 8). Increase in size now overtakes the newly active 

 cells, and a simple outgrowth emerges exogenously, this gradually in- 

 volving the whole of the base of the tentacle (Vickery) {16 — 9, 10). 

 The vegetation point having been defined at the scene of the earliest 

 divisions, this is now raised by the growth activities of the paren- 

 chyma of the upper moiety of the mother leaf in the immediate vicinity, 

 carrying up the tentacle so that this now appears to arise from the bud, 

 rather than the bud from it. Whether the new vascular tissue, that of 

 the bud, becomes articulated with the older, that of the leaf, is not 

 clear. Doubtless this occurs if the leaf does not decay, as observed by 

 Vickery. If, however, the leaf does decay, this may be questioned. 

 Robinson (1909) asserts that no connection occurs. The vegetation 

 point having been established, leaves appear on the bud and a new 

 plantlet becomes established, roots being formed secondarily. The 

 earlier leaves frequently show abnormalities, as I have observed, 

 such as the lateral fusion of contiguous leaf primordia, producing more 

 or less laterally doubled leaves. Nepionic leaves occur. Leavitt 

 (1903) was able to produce such even from the terminal bud by cutting 

 off the stem below it and removing the leaves as they expanded. D. 

 intermedia, which bears only radially symmetrical tentacles normally, 

 under such condition of ''malnutrition " bears on nepionic leaves 

 spoon-shaped lateral tentacles like those of D. rotundifolia. The fre- 

 quency and ease with which all this occurs, as already mentioned, 

 makes it probable that this method of reproduction rivals, in its re- 

 sults, reproduction by seed. I have at my hand now a small flower 

 pot which a few months ago carried three small plants sent to me from 

 Ontario by my friend Professor R. B. Thomson. These at the present 

 writing have died down to winter buds, and I count at least a dozen 

 minute plantlets which I observed to have arisen from old and at 

 length decaying leaves. 



Behre has further described the origin of plantlets from the leaf 

 stalk. As in the case of the blade, such always occur on the upper 

 surface, with the exception of D. capefisis and D. binata, in which they 



