ANALYTICAL KEY. 29 



Ovary really free from the calyx, but pej;manently invested by its 

 tube, or the base of it, so as to seem inferior. 

 Shrubs, with scurfy leaves : flowers mostly dioecious. El^eagnace^, 424 

 Herbs : with the calyx colored like a corolla. 

 Leaves opposite, simple.' '..... Nyctaginace^, 404 



Leaves alternate, pinnate Poterium, in RosACEiE, 1 46 



Ovary plainly free from the' calyx, which is sometimes wanting. 

 Stipules (ochrese) sheathing the stem at the nodes. 

 Tree : the calyx none ; flowers monoecious, in heads. Platanace^, 446 

 Herbs': the calyx present and commonly petal-like. Polygonace^, 414 

 Stipules not sheathing the stem, or none. 

 Aquatic herbs, submersed or nearly so. 

 Leaves whorled and dissected : style single. Cbkatophtllace;e, 427 

 Leaves opposite, entire : styles 2 ; ovary 4-celled. Callitkichace^, 427 

 Not aquatics, herbs. 

 Ovary 10-celled : berry 10-seeded. . . . PnYTOLACCACEjs, 405 

 Ovary 3- (rarely 1 - 2-) celled : juice usually milky. EnPHOEBiACE.E, 430 

 Ovary one-celled : juice not milky. 

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



no scarious bracts around the flowers. . . Ueticace.s), 440 

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

 Stipules not scarious ; leaves palmately cleft or 



palmately compound. . Cannabinese, in UKTiCACEiE, 440 



Stipules scarious. . . lUecebreae, in Cakyophyllace^, 87 

 Stipules and scarious bracts none : stamens inserted high up 



on the tube of the calyx. Scleranthus, in Cakyoph YLLACEiE, 87 

 Stipules none : but flowers with scarious bracts. Amaraktace^, 411 

 Stipules and scarious bracts none . . CHENOPODiACE.a:, 405 

 Shrubs or trees. 

 Ovules a pair in each cell of the ovary. 

 Fruit 2-celled, a double samara. Acerinese, in Sapindace^, 116 



Fruit a 1 -celled and 1 -seeded samara or a drupe. Oleace.^, 400 



Ovules single in each cell of the 

 Three -nine-celled ovary : leaves heath-like. . Empetkace^, 440 

 Three-celled ovary : leaves broad. . . . Ehamnace^, 113 

 One - two-celled ovary : styles or stigmas 2-cleft. Urtioace^, 440 

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

 Anthers opening longitudinally . . . Thymeleace.*, 424 

 Anthers opening by uplifted valves. . . . LAURACEa), 422 



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 strobUe. . . Urticace^, 440 



Fertile flowers single or clustered : sterile ones in slender catkins. % 



Leaves pinnate : fertile flowers and fruit naked. . Jdglandace^, 447 



Leaves simple : fertile flowers 1 - 3 in an involucre or cup. CupuLiFEaa;, 449 



