THE STEM OR SHOOT. 



118 



reversions to the more ancestral and original condition 

 in which the shoot was very much less modified in 

 function and therefore in form, and much less 

 reduced in length, than it is at the present clay. As 

 we shall see later to be the case with the inflorescence 

 and the flower, the evolution of axile organs has 

 involved a vast amount of stereotyping, and reduction 

 in one form and another, for the benefit of the plant 

 as a whole. Practically none of the cases of axillary 

 proliferation can be regarded as ancestral, for they 

 nearly all exhibit peculiar forms which are not likely to 

 have occurred in the ancestors of the plant concerned, 

 and are generally, moreover, due to the influence of 

 very special stimuli. They represent special adapta- 

 tions to the abnormal conditions, and they all show 

 what the potentialities of the plant in this direction are, 

 under certain conditions of the environment. The cases 

 of Passiflora and Gycas are exceptions in this respect. 



BIBLIOGRAPHY. 



Aitchison. — "On the Flora of the Kuram Valley, etc., 

 Afghanistan/' Journ. Linn. Soc, vol. xix (1882), p. 140. 



Andy, S. Pulny. — "On Branched Palms in Southern India/' 

 Trans. Linn. Soc, vol. xxvi (1869), p. 661. 



Anon. — "Leucojum sestivum." Gard. Chron., n. s., vol. xiii 

 (1882), p. 155. 



"Passion-flower coming on a Tendril." Ibid., ser. 3, 



vol. xxiv (1898), p. 27. 

 Braun. — " Ueber einen Kartoffelstengel mit Knollen in den 



Achseln oberirdischer Blatter." Schriften physik. oekon. 



Ges. Konigsberg, Bd. xviii (1877), p. 58. 

 Bruchmann. — Untersuchungen uber Selaginella spinidosa 



A.Br. Gotha, 1897. 

 ■ " Von den Wurzeltragern der Selaginella Kraussiana 



A.Br." Flora, Bd. xcv, Erganz. (1905), pp. 150-151, pis. 



v, vi. 



" Vom Proth allium der grossen Spore und der 



Keimesentwicklung einiger Selaginella-nvteTi. ,} Flora, 

 Bd. xcix (1908), p. 12. 



Carriere. — " Bourgeonnement et ramification des feuilles de 

 Sciadopitys verticillata." Revue horticole, 1884, p. 16. 

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