OVULIFEROUS STRUCTURES OF TAXUS CANADENSIS . 



CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 267 



A. W. Dupler 



(WITH PLATE XXIII AND SIXTY FIGURES) 



Introduction 



Following a recent paper (13) in which the writer gave a descrip- 

 tion of the staminate structures of Taxus canadensis Marsh., this 

 paper deals with the ovuliferous structures, namely, the primary 

 shoot, the secondary shoot, and the ovule, describing both the 

 development and vascular features, together with a discussion of 



the morphological questions raised by these, structures. The 

 purpose in this investigation was twofold: (1) to compare T. cana- 



_ • 



densis with the European T. baccata, and (2) to look for new evi- 

 dence bearing on the morphological problems of these structures 

 in. the genus. While no pretense of finality is made in this con- 

 nection, it is thought that some additional evidence has been 

 secured bearing on these problems. Since the female gametophyte 

 has already been described (12), only such reference is made to it 

 as may be necessary. For a statement as to materials and methods, 

 the reader is referred to previous papers (12, 13). 



Historical 



gametophytes, and the 



ng time, the 

 embryogeny 



especially receiving attention. The literature dealing with the 



structures is quite extensive, much of it being 



and 



is based almost entirely upon T. baccata, very little dealing spe- 

 cifically with T. canadensis. The two forms are similar (6), and 

 much which has been written will annlv pniiallv well to both forms. 



Botanical Gazette, vol. 69] 



summary ot all tnai 

 summary sufficing, 



[492 



