ANALYTICAL KEY. 27 



Ovary 1-celled; juice not milky. 



Style, if any, and stigma only one ; leaves simple ; 



no scarious bracts around the flowers. . URTICACE.S:, 461 

 Styles 3 ; embryo straight ; flowers involucrate. 



Eriogonum, in POLYGONACE.S;, 436 

 Style or stigmas 2 or 3 ; embryo coiled or curved. 

 Stipules not scarious, leaves palmately cleft or 



palmately compound. . . Cannabinere, in URTICACE^E, 461 



Stipules scarious (or none) ; leaves opposite. ILLECEBRACE^:, 426 



Stipules none; but flowers with scarious bracts. AMARANTACE>E,427 



Stipules and scarious bracts none . . CHENOPODIACE.E, 430 



Shrubs or trees. 



Ovules a pair in each cell of the ovary. 



Fruit 2-celled, a double samara. Acerineae, in SAPINDACE.E, 115 

 Fruit a 1-celled and 1-seeded samara or a drupe. OLEACE^E, 335 



Ovules single in each cell of the 



Three - nine-celled ovary ; leaves heath-like. . EMPETRACE^;, 487 

 Three-celled ovary ; leaves broad. . . . RHAMNACE^E, 111 

 One - two-celled ovary ; styles or stigmas 2-cleft. URTICACE^E, 461 

 One-celled ovary; style and stigma single and entire. 



Anthers opening longitudinally. . . THYME LJEACE^;, 448 

 Anthers opening by uplifted valves. . . . LAURACE^E, 446 



B. Flowers monoecious or dioecious, one or both sorts in catkins. 

 1. Only one sort of flowers in catkins or catkin-like heads. 



Fertile flowers in a short catkin, head, or strobile. . . URTICACE^E, 461 



Fertile flowers single or clustered ; sterile in slender catkins (except in Fagus). 



Leaves pinnate ; fertile flowers and fruit naked. JUGLANDACE.E, 467 



Leaves simple ; fertile flowers 1-3 in an involucre or cup. CUPULIFERJE, 470 



2. Both sterile and fertile flowers in catkins or catkin-like heads. 



Ovary and pod 2-celled, many-seeded. Liquidambar, in HAMAMELIDE^E, 180 

 Ovary and pod 1-celled, many-seeded ; seeds furnished with 



a downy tuft at one end SALICACEJE, 480 



Ovary 1 -2-celled, only one ovule in each cell; fruit 1-seeded. 



Parasitic on trees ; fruit a berry. .... LORANTHACE^E, 449 



Trees or shrubs, not parasitic. 



Calyx regular, in the fertile flower succulent in fruit. URTICACE^E, 461 

 Calyx none, or rudimentary and scale-like. 



Style and stigma one, simple ; the flowers in heads. PLATANACE^E, 466 

 Styles or long stigmas 2. 



Fertile flowers 2 or 3 at each scale of the catkin. CUPULIFER^E, 470 

 Fertile flowers single under each scale ; nutlets 



naked, waxy-coated or drupe like. . . . MYRICACE^;, 469 



SUBCLASS IT. GYMNOSPERM 2E. Pistil an open scale or altered 

 leaf, bearing naked ovules on its margin or its upper surface, or in Taxns 

 entirely wanting. Flowers monoecious or dioecious. CONIFERS, 489 



