1920] DUPLER—TAXUS CANADENSIS 493 



more complete references being available in the accounts of 

 Strasburger (35), Radais (24), and Worsdell (39). 



The earlier work was based largely on external features, and 

 attempted to homologize the structures with those of the angi- 

 osperm flower. This attempt 



seemi 



most other conifers, the gymnospermy 



the literature deals with 



gnized as in other forms. The bulk of 



more 



eing so extensive. The discussion of the 



in 



m 



more complete form 



Ovuliferous bud 



As previously pointed out (13), three types of buds are formed 

 in the axils of the leaves of a current season's shoot, namely, vegeta- 

 tive, staminate, and ovuliferous. The differentiation of the last is 

 first recognized by the appearance of the rudiment of a secondary 

 axis in the axil of one of its uppermost scales (fig. 1), this rudiment 



July. The o^ 

 1 rudiment in 



in 



after the beginning of the growth of the vegetative shoot, forming 

 usually nearer the tip than the staminate buds. Strasburger 



(36) found the first differentiation of the ovuliferous bud in 

 T. baccata to occur about August 1. The structure can be dis- 

 tinguished by external features with certainty only when the 

 ovule has reached such size as to protrude beyond the scales, 

 usually not until spring. Jager (15) says that the ovuliferous bud 

 of T. baccata is evident about February 1, being slightly yellowish, 

 and the vegetative bud being reddish brown; but this is hardly a 

 safe criterion, owing to color variations. 



Primary shoot 



General features. — The ovuliferous oreran in 



D 



of two structures : 



more 



known, the primary shoot; and the secondary 



ovule is borne. The primary shoot arises directly 



