ANALYTICAL KKY. 29 



Ovary really free from tlie calyx, but permanently invested by its 

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

 Shrubs, with siurfv leaves : flowers mostly diceeious. El.kagnaci:.«, 424 

 Herbs : with the ealyx colored like a corolla. 



Leaves opposite, simple. ..... Nyctaginace.e, 404 



Leaves alternate, piiniate Poterium, in Rosacea;, 146 



Ovary plainly free from the ealyx, which is sometimes waiitin;,'. 

 Stipules (oclirea^) sheathinj,' the stem at the nodes. 



Tree : tlie calyx none : tlowers monu;cious, in heads. Pi-ATANAricK, 446 

 Herbs: the calyx jiresent and commonly petal-like. Polyoo.nacl.k, 414 

 Stipules not sheathing the stem, or none. 

 Aipiatie herbs, submersed or nearly so. 



Leaves whorled and dissected : style single. CERAToriiYi.i.ACK.T;, 427 

 Leaves opposite, entire : styles 2 : ovary 4-cellcd. Cali-ituiciiacici:, 427 

 Not acjuatics, herbs. 



Ovary 10-celled: berry 10-sccded. . . . riiYxoLACCACK^v, 405 

 Ovary 3- (rarely 1 - 2-) celled : juice usually milky. Eui'iioBBiACiiiE, 430 

 Ovary one-celled : juice not milky. 



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



no scarious bracts around the flowers. . . Urticace^., 440 

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

 Stipules not scarious ; leaves palmately cleft or 



palmately compound. . Cannabinea;, in Urticace^, 44C 



Stipules scarious. . . Illocebrea!, in Caryophyllace.*:, SJ 



Stipules and scarious bracts none : stamens inserted high up 



on the tube of the calyx. Selcranthus, in Caryoi'IIYLLACE.e, 87 

 Stipules none : but flowers with scarious bracts. Amakan'tace;e, 411 

 Stipules and scarious bracts none . . Cuenopodiace.i:, 405 

 Shrubs or trees. 

 Ovules a pair in each cell of the ovarj'. 



Fruit 2-celled, a double samara. Accrinea?, in Sapindace.t:, 116 



Fruit a 1-celled and 1 -seeded samara or a drupe. Oleace.i:, 40tt 



Ovules single in each cell of the 



Three -nine-celled ovary : leaves hcatb-likc. . Empetrace.i:, 440 

 Three-celled ovary : leaves broad. . . . Riiamxace.e, ll.*) 



One- two-celled ovary : styles or stigmas 2-cleft. Ui;ticace.k, 440 

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



Anthers opening longitudinally . . . TuvMr.i.EACE.E, 424 

 Anihers opening by uplifted valves. . . . Laiuace.e, 422 



B. Flowers {monacioiis or diwcioiis) one or both sorts in calkins. 



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



"Fertile flowers in a short catkin, head, or strobile. . . Urticace.e, 440 

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



Leaves pinnate : fertile flowers and fruit naked. . Jcglandaoe.e, 447 



Leaves simple ; fertile flowers I -3 in an involucre or cup. CuPULiFKRJi, 449 



