No. 508] 



STUDY OF VASCULAR ANATOMY 



with the elucidation of the affinities of extinct plants. 

 Certain cryptogamic trees of the Paleozoic, the Lepido- 

 dendrids, Sigillarians and Calamites, were, for example, 

 long regarded by competent botanists as seed plants on 

 account of their arboreal habit. The anatomists stoutly 

 maintained, however, that from the structure of their 

 primary wood they must be cryptogams. The subse- 

 quent discovery of their reproductive structures entirely 

 confirmed the anatomical view. More recently from the 

 study of the anatomy of certain fern-like plants with 

 secondary growth, from the Paleozoic, English and Ger- 

 man anatomists reached the conclusion that they were 

 gymnosperms and allied at once to the ferns and to the 

 cycads. Within the past decade, the brilliant discoveries 

 of Oliver, Scott, Kidston, Grand 'Eury and David White 

 in regard to the nature of the reproductive organs of 

 these plants, prophetically dubbed by Potonie, the Cyca- 

 dofilices, have confirmed the truth of the anatomical view 

 as to their affinities in every particular. Let us take a 

 still more modern instance. There are present m the 

 later Mesozoic strata huge quantities of impressions of 

 the cones and leafy twigs of conifers. These have been 

 referred on features of superficial resemblance to a num- 

 ber of genera of living conifers as well as to others not 

 represented in the existing flora. Since they are very 

 numerous, let us take one typical example, which is at the 

 time significant. Many species of Sequoia have 

 and the Ore- 



been described from the upper Jurassic 



taceons beds, on the evidence of the impress upon the 

 stony or argillaceous matrix of their cones and leafy 

 branches. Dr. Arthur Hollick and the present speaker 

 have been fortunate enough to secure by new methods ot 

 isolation, material of these cones and twigs, with internal 

 structure preserved. The anatomical features of both 

 reproductive and vegetative organs of i the remains in 

 question, show beyond any possible doubt that they be- 

 long to a tribe of conifers at present confined to the 

 southern hemisphere, the Norfolk Island and Kaun Pines 



