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WEEDS AND USEFUL PLANTS. 



1. PI'NUS, L. PINE. 



[The classical Latin name.] 



Flowers monoecious. STAMINATE AMENTS clustered in terminal spikes. 

 Stamens numerous, inserted on the axis ; anthers subsessile, 2-celled, 

 opening lengthwise, covered at apex by the dilated scale-like connective. 

 FERTILE AMENTS solitary or clustered ; the carpellary scales with de- 

 ciduous bracts and each bearing a pair of inverted ovules at its base. 

 Fruit a cone formed of the woody scales which are thickened at apex 

 (except in the White Pines), persistent and spreading when ripe and 

 dry ; the nut-like seeds partly sunk in an excavation at the base of each 

 scale, and winged by an adhering portion of its lining. Cotyledons 3-12, 

 linear. Trees with leaves in bundles of 2 - 5, needle-shaped, each fascicle 

 from the axils of a chaffy scale. Fruit generally maturing in the au- 

 tumn of the second year after flowering. 



* Leaves 2-3 (rarely 4) in a sheath : bark rough : cones woody, scales 

 thickened at me end and mostly tipped with a spine. 



f Leaves in twos, except in No. 3. 



1, P. in'ops, Ait. Leaves rather short ; strobiles oblong ovoid, often 

 curved ; spines of the scales slender and straight. 



FIG. 233. A branch of a Pine with stamiuate amonts at the top. 234. A stamen. 235. 

 A branch with pistillate aments at the apex and the fruit (cone) below. 236. A scale 

 from the fertile ament with two ovules at its base. 237. Scale from a ripe cone, with one 

 of the two seeds removed. 238. The germinating embryo of a Pine, with several cotyle- 

 dons. 



