igig] DUPIER—TAXUS 347 



layers of irregular cells, and states that dehiscence is accomplished by • 

 the rupture of cells at the base and sides of the pollen sac. Cham- 

 berlain (3) describes the microsporangium of T. canadensis at the 

 mother cell stage (October 1, 1897), at which time the nuclei are 

 still rather small in comparison with the size of the cell, the tapetum 

 being sharply differentiated, and its cells showing no tendency to 

 plasmolyze like the cells of the sporangium wall. Pilger (18) 

 describes the general external features, largely from the taxonomic 

 viewpoint, speaking of the "flower" as consisting only of sporo- 

 phylls surrounded at the base by a scale envelope which com- 

 pletely incloses the flower in the bud state. He regards the "leafy 

 structure" of the anther, which is yet to be recognized in Torreya 

 and Cephalotaxus, as being "entirely lost" in Taxus. 



In the related forms the staminate structures of Torreya have 

 been described in a general way by Pilger, based on T. nucljera; 

 in more detail by Miss Robertson (20) for T. calijornica; and 

 by Coulter and Land (5) for T. taxifolia. In Cephalotaxus 

 some of the features of the spermatogenesis have been described by 

 Strasburger (23), and by Arnoldi (i). Strasburger (24) 

 pointed out that the pollen grain divides in the sporangium before 

 shedding; Lawson (14) also confirms this in C. drupacea; and 

 Worsdell (27) gives a description of the general features of the 

 "male flower," based on C. Fortunei, comparing it with those of 

 other forms (Phyllocladus and Ginkgo), especially in the sporophyll 

 features. 



Strobili buds 



In the axils of the leaves of the shoot of a given season 3 types 

 of structures are produced: (1) the vegetative buds from which 

 develop the lateral leafy shoots of the next season; (2) the young 

 staminate structures, maturing the next season; and (3) the ovule- 

 bearing structures, also maturing the next season. During the first 

 season all of these structures are in bud form, the staminate buds 

 during the latter part of the summer and winter being more globular 

 than the other two kinds, which are so nearly alike in .external 

 appearance as to make their distinction uncertain except by very 

 careful examination. 



