532 



BOTANY OF THE LIVING PLANT 



pollination, matures into the hard woody cone, from which the name 

 Coniferae is derived (see Figs. 414, 416). When ripe it consists of a 

 central axis bearing in a complex spiral numerous woody ovidiferous 

 scales. As the cone ripens the scales turn back, and two seeds may 

 be seen freely exposed on the upper surface of each. When fully 

 ripe each seed separates from the scale, together with a thin film of 

 superficial tissue, which on detachment helps to float it away on 



SM 



Fig. 419. 



Radial section of Pine stem, at the junction of wood and bast. Phloem to 

 the left, xylem to the right. s = autumn tracheides. *=bordered pits. c= 

 cambium. r=sieve tubes. itf=sieve pits, tm = tracheidal medullary ray cells. 

 sm= medullary ray cells in the wood containing starch. sm' = the same in the 

 bast. £wi=medullary ray cells with protoplasmic content. ( x 240.) (After 

 Strasburger.) 



the breeze (Fig. 4 14, B). The seed is protected by a seed-coat, covering 

 a bulky endosperm, with a large embryo enclosed in it, which has 

 many cotyledons, a plumule and radicle. The seed is thus " albu- 

 minous," and in essential points it corresponds to that of Angiosperms. 

 But in the Scots Pine it takes two years to produce, and the details 

 of its production give important features for comparison. 



Both the types of flower are axillary in their origin. The male 

 flowers are produced in large numbers, replacing the weak foliage 

 spurs (Fig. 420). The female take the place of the stronger branches 

 of unlimited growth, and are produced in smaller numbers (Fig. 416). 



