Trees of New York Stale 347 



stamens, each with 2 pollen sacs and apiculate connective; ovulate flowers 

 siibglobose, consisting of a few or many, nearly orbicular, stalked, green, 

 ovuliferous scales subtended by scarlet, projecting, mucronate bracts; ovules 

 2, inverted. Fruit an ovoid-oblong, woody, short-stalked, erect cone, maturing 

 the first season; cone scales thin, concave, reduced to sterile bracts at the 

 base of the cone; seeds nearly triangular, shorter than their wings; 

 cotyledons G. 



THE SPRUCES. Genus PICEA Link. 

 The genus Picea consists of eighteen species confined wholly to 

 the cooler parts of the north temperate and subarctic zones, often 

 forming extensive forests on mountain slopes and plains. Seven 

 species are native to North America, three of which occur in New 

 York State. 



Leaves persistent., linear, 4-sided, stomatiferous on all faces, spirally 

 arranged and coming out from all sides of the twig, or occasionally appearing 

 2-rajiked due to a twist in the petiole, articulated to persistent leaf-bases. 

 Floivers terminal or in the axils of the upper leaves, monoecious, vernal; 

 staminate flowers cylindrical, usually long-stalked and subtended at the base 

 by accrescent bud-scales, consisting of numerous, spirally arranged stamens 

 with 2 pollen sacs and connective produced distally into a broad, nearly cir- 

 cular, toothed crest; ovulate flowers oblong, oval, or cylindrical, the ovuli- 

 ferous scales rounded or pointed and subtended by bracts; ovules 2, inverted. 

 Fruit an ovoid or oblong-cylindrical, pendant, woody cone, maturing the first 

 season, generally crowded on the uppermost branches; cone-scales thin, con- 

 cave, unarmed, entirely concealing the bracts at maturity; seeds ovoid or 

 oblong, acute at the base, much shorter than their wings; cotyledons 4-16. 



KEY TO THE SPECIES page 



1. Branchlets glabrous and usually glaucous; cones oblong-cylindric 91 



P. canadensis 



1 . Branchlets pubescent ; cones ovate or ovate-oblong 2 



2. Foliage yellowish green or dark green; cones elongated-ovoid, reddish 



brown P. rubra 93 



2. Foliage bluish green and glaucous; cones short-ovoid or sub-globose, duU 



ashy brown P. mariana 95 



THE HEMLOCKS. Genus TSUGA (Endl.) Carr. 

 Tsuga is represented by seven species which are scattered over 

 temperate North America, Japan, central and western China and 

 the Himalayas. Four species occur in the United States, two 

 eastern and two western forms respectively. The hemlocks are 

 trees with pyramidal crown, horizontal or drooping branches and 

 horizontal, flat sprays of foliage. The bark is rich in tannin. 



Leaves persistent, linear, flat or angular, acute, obtuse or emarginate at 

 the apex, stomatiferous in two white bands below or on both faces in Tsuga 

 Mertensicna, spirally arranged but usuaJly appearing 2-ranked by a twisting 

 of the petioles, those on the upper side of the branchlet much shorter, abruptly 



