v LINN^EAN ARRANGEMENT 



by 1 2 beaks. Corolla filiform. Stamens none. Achenia compressed, 

 one in each cell of the involucre. Composite, p. 183. 



AMBROSIA. Fertile heads at the base and sterile ones at the top of the 

 spike. STERILE FL. Involucre hemispheric or turbinate ; scales few. 

 Receptacle naked. Corolla tubular, short. FERTILE FL. Involucre 1- 

 flowered, incurved and often armed with several tubercles or horns. Corolla 

 none. Achenia ovoid or obovoid. Composite, p. 184. 



(Fagus and Quercus in ORDER POLYANDRIA.) 



ORDER VI HEXANDRIA. 6 Stamens. 



ZIZANIA. Flowers glumaceous. Spikelets 1-flowered. STERILE FL. 

 Glumes none, or only rudimentary. Paleae 2, herbaceous, concave, nearly 

 equal, awnless. PERFECT FL. Glumes none. Palese 2, herbaceous ; 

 lower one longer, oblong, keeled, terminating in a straight awn. Styles 2, 

 short. Graminacea;, p. 4 19. 



ORDER VII. POLYANDRIA. Many Stamens. 



* Siems not woody. 



CERATOPHYLLUM. Calyx inferior, many-parted. Corolla none. STE- 

 KILE FL. Stamens 12 20; filaments wanting. FERTILE FL. Stigma 

 filiform, oblique. Fruit a beaked achenium. Ccratophyllacea, p. 114. 



MYRIOPHYLLUM. STERILE FL. Calyx 4-parted. Petals 4, ovate, some- 

 times inconspicuous or wanting. Stamens 48. PERFECT FL. Calyx ad- 

 hering to the ovary ; limb 4-lobed. Petals none. Nuts 4, compressed or 

 subglobose, 1-seeded. Haloragacece, p. 1 12. 



SAGITTARIA. Perianth 6-leaved ; 3 outer leaves persistent, calycine ; 3 

 inner colored, petaloid. FERTILE FL. Ovaries collected into a head. Car- 

 pels compressed, 1-seeded, crowned with the persistent style. Alismacecc, 

 p. 378. 



ARISJEMA. Spathe convolute below, the limb arched or flatfish. Spa- 

 dix naked above, the lower part covered with flowers, of which the upper 

 are sterile and the lower fertile, or in some plants all sterile. Anthers some- 

 what verticillate and distinct. Stigma nearly sessile. Berry J several- 

 seeded. AracecE, p. 381. 



PELTANDRA. Spathe elongated, convolute, undulate on the margin, 

 curved at the apex. Spadix covered with flowers. Perianth none. An- 

 thers sessile, covering the upper part of the spadix in a tesselated manner. 

 Ovaries 1-celled, on the lower part of the spadix. Berries ovoid, forming a 

 dense cluster. Aracctf, p. 382. 



CALLA. Spathe ovate, somewhat flattened. Spadix covered with flowers 

 which are destitute of a perianth, and consist of pistils surrounded by sta- 

 mens. Berries distinct, depressed, few-seeded. Aracecz, p. 382. 



** Stems woody. (Trees or Skrubs.} 



OBS. The genera of this division are included in the Natural Orders 

 Cupuliferte, p. 326 ; Platanaceee, p. 333 ; Altingiacea t p. 333 ; and Jtiglan* 

 dacea, p. 335. 





