248 PBACTIGAL BOTANY. 



Pistil closed ; ovules, or seeds, enclosed. Sterile 

 flowers either in aments, or spikes, or rarely solitary ; some- 

 times clustered in the axils 782 



777. Fertile scales many, each subtended by a bract, 

 with 2 inverted ovules. Seeds winged 778 



Fertile scales few, bractless, each with 2 to 8 erect 

 ovules 780 



778. Leaves evergreen ,. . 779 



Leaves deciduous, filiform, very slender, many in 



the fascicles, on short, lateral branchlets. The sterile flow- 

 ers with 2-celled anthers, their cells opening lengthwise. 

 Cones erect, ovoid ; scales colored, persistent. 



Iiarix Americana, Mx. 



779. Leaves fascicled, 2-5 together. Sterile aments in 

 terminal clusters ; stamens many ; anthers 2-celled, with a 

 scale-like connectile ; pollen of 3 united grains. Fertile 

 aments (cones) conical, or cylindric, the carpellary scales 

 bracted, imbricate, often thickened or awn-pointed at the 

 tip, at length hardened. Seed nut-like. Finus. 



Leaves separate, scattered. Sterile aments axillary, 

 clustered toward the ends of the branches. Scales of the 

 fertile aments (cones) flat, not thickened, nor awn-pointed. 



Abies. 



780. Leaves evergreen, scale-like, or awl-shaped. Flow- 

 ers monoecious on difierent branches. Filaments scale-like, 

 with 2-4 anther-cells. Branchlets 2-edged, compressed. .781 



Leaves deciduous, linear, 2-ranked. Flowers 

 monoecious on the same branches. Scales of the fertile, 

 closed, clustered aments with 2 ovules at the base. Sterile 

 aments spikedpanicled, of few stamens ; filaments scale- 

 like, peltate^ bearing 2-5 anther-cells. 



Taxodium distichum, Eicli. 



781. Scales of the globular, closed cones in 4 ranks, 

 shield-shaped, angular, bearing 4-8 bottle-shaped, erect 

 ovules at the base inside. Cones opening at maturity. 

 Leaves flat, squamous, tuberculate at the base, imbricated. 



Cupressus thyoides, L. 

 Scales of the ovoid cones few, imbricated, oblong, 



