president's address. 793 



8. — Comparative Study of Seedlings and Suckers 

 (A Phase of Ontogeny). 



" I would call attention to recent researches in plant ontogeny; 

 the investigation of embryonic develo23nient, the comparative 

 study of seedlings, and such observations as have been recently 

 made by Prof.^ R. T. Jackson upon the reappearance of juvenile 

 and ancestral traits in offsets and runners."* 



Dr. Robinson then points out that while systematic zoologists 

 have long made use of ontogeny in determining group affinities, 

 botanical taxonomists have been much less successful in drav/ing 

 from the early stages of plants like inferences. " Ontogeny has 

 for the plant-taxonomist a wealth of information as yet unrevealed 

 regarding the affinities of genera within the family, and species 

 within the genus. . . . The form, position, and venation of 

 leaves, the nature of the petioles, stipules, pubescence, and glan- 

 dularity, all shown in the seedling, are significant." Let me 

 draw attention to this fascinating field of enquiry in Australia. 

 The only genus, as far as I am aware, in which observations have 

 been systematically made in this direction is Eucalyjjtus. Mueller 

 drew attention to the value of seedlings and suckers for diagnostic 

 purposes, and Mr. Deane and I may fairly lay claim to have 

 insisted on their great importance in taxonomic work. Lubbock's 

 work on seedlings will at once occur to one in this connection. 

 Mr. L. Cockaynef has recently published some valuable observa- 

 tions on seedlings in continuation of his former researches, while 

 at the Sydney Botanic Gardens I have inaugurated a systematic 

 examination of seedlings. The study of suckers and seedlings 

 places a powerful weapon in the hands of systematists in the 

 classification of plants. It is obvious, of course, that the experi- 

 menter who undertakes this line of research should either be a 

 good systematist himself, or should co-operate with one. I have 



* Prof. B. L. Robinson, op. cit. 

 + An Inquiry into the Seedling Forms of New Zealand Phanerogams and 

 their Development. Tram. N.Z. Instit. xxxiii. 265. 

 52 



