4- 



PHANEROGAMS. 



B. CONIFERS ^ 



Gcnninatian. The endosperm surrounds the embryo in the form of a thick- 

 walled sac open at the radicular end ; the embryo lies straight in the central cavity of 



P re. 316.— />/«7cj- Pi7iea ; / longitudinal section through the middle of the seed, y the micropylar end ; // commencement 

 of gerniMiation, emergence of the root ; /// completion of germination, after the endosperm has been absorbed (the seed 

 lay at too small a distance below the surface, and was therefore raised up by the cotyledons when the stem began to grow) ; 

 A shows the ruptured testa s, B the endosperm e, one half of the testa having been removed, C longitudinal section 

 of the endosperm and embryo, D transverse section at the commencement of germination ; c the cotyledons, tu the 

 primary root, x the embryo-sac pushed out by it (ruptured ni B), he hypocotyledonary portion of the axis, w' secondary 

 roots, r red membrane within the hard testa. 



the endosperm ; its axis is continuous behind with the rudiment of the primary root, 

 and bears at its anterior end a whorl of two or more cotyledonary leaves, between 



' For the structure of the flowers, see R. Brown, On the Phuah'ty and Development of the 

 ibryos in the Seeds of Conifera^: Misc. Bot. Works, London, 1S66, vol. I, pp. 567 576.— H. von 



