594 



BOTANY 



PART II 



the sporophylls of which are swollen and succulent ; one or two sporophylls bear at 

 the summit a single anatropous ovule surrounded by a fleshy arillus. The male 

 flowers, which are borne on the same or on distinct individuals, are small cones 

 consisting of numerous sporophylls attached to a short erect axis. Each sporophyll 

 bears two microsporangia on the lower surface ; the microspores are provided with 

 distended wings. 



Taxus baccata is the only European representative of the family. The Yew, 

 which is now for the most part artificially introduced, had formerly a wide distribu- 

 tion as an evergreen undergrowth in our native woods (Figs. 585, 586). The 

 Yew tree attains a height of 10 m. Isolated examples of large size occur. All 



FIG. 586. Taxus baccata, bearing fruits. (jnat. size.) 



the branches are shoots of unlimited growth. The leaves stand on all sides of 

 the ascending main shoots, but in two rows on the horizontally-expanded lateral 

 branches. They are narrow, flat leaves and persist for several years. The tree is 

 dioecious ; the flowers are situated on the lower surface of the twigs and arise in the 

 axils of the leaves of the preceding year. The male flowers are invested at the base 

 by a number of scale leaves and contain some 10 peltate stamens, each of which 

 bears 5-9 pollen sacs. The mode of opening of the sporangia is peculiar. The outer 

 wall splits at the base and along the side of each pollen-sac, so that the whole stamen 

 resembles an umbrella turned inside out ; the pollen remains for a time in the 

 pocket -like depressions, from which it is removed by the wind. The female 

 flower usually develops singly as a secondary, axillary shoot of the uppermost 



