SUBDIVISION SECOND. 



ENDOGENS, OR MONOCOTYLEDONOUS PLANTS. 



Stem not distinguishable into bark, pith and concentric zones or 

 layers of wood. Growth by irregular, internal accretions, consist- 

 ing of bundles of woody fibre and vessels, successively descending 

 from the leaves above, through the cellular tissue already formed. 

 Leaves mostly with simple, parallel veins, alternate, entire, frequently 

 sheathing at base, and seldom falling off by an articulation. Sepals 

 and PETALS, when present, commonly in 3s. Ovules produced within 

 an ovary. Embryo with one cotyledon, rarely with two, the second 

 being much smaller than, and alternate with, the first. 



CLASS III. AGLUMACEOUS ENDOGENS. 



Flowers without glumes. Organs developed on the usual and 

 normal plan, consisting of stamens and pistils, either or both, sur- 

 rounded by verticillate, floral envelops ; or the latter are wanting, 

 and the stamens and pistils are achlamydeous. 



Order CXXXIV. ARACE^.— Arabs. 



Herhs or tropical shrubs, with a fleshy rhizoma or cormus. 



Lvs. sheathing at base, often with branching veins, and sometimes compound. 



FIs. mostly monoecious and achlamydeous, arranged upon a naked or spathaceous spadix. 



Perianth, when present, consisting or4— 6 i)arts. 



Sta. definite or indefinite, hypogynous, very short. Anth. ovate, extrorse. 



Ore. free, 1— several-celled. Srig-wm sessile. 



Pr.—Berri- succulent or dry. Seeds solitary or several, with fleshy albumen. 



Genera 26, species 170, abundant in tropical regions, more rare in temperate, one only, Calla palustris, 

 extending to the northern frigid zone. 



Proper/ies.— An acrid, volatile principle pervades the order, which is, in some instances, so concen- 

 trated as to become poisonous. The corms and rhizomas abound also in starch, which in some cases, 

 when the volatile acridity is expelled in drying or cooking, is edible and nutritious. 

 Conspectus of the Genera. 



< Berry 1 seeded. . Peltandra. 2 



I and covered 4 cylindric. { Berry many-seeded. Calla. S 



■; w ith flowers, ( oval, preceding the leaves. . Symplocarptu. 6 



{ Ppadix in a spathe ( and naked above. Stem a corm. . . . Arum. 1 



^ broad. ( Spadix naked, yellow, on a clavate scape. Oronliwii. 4 



Leaves { linear-ensiform. Scape leaf-like. Spadix lateral. Acorus. 6 



1. ARUM. 



Coptic aron, the name of the Egyptian species, A. colocasia. 



Flowers sometimes 9 c^. Spathe cucullate, convolute at base ; 

 perianth ; spadix cylindric, naked above, staminate below the mid- 

 dle and pistillate at the base; berry 1-celled, many-seeded. — %. 

 1. A. TRiPHYi.LL'M. Drai^on-Fiool . Jack-in-the-PvlpU. 

 Acaulescent; lvs. trilbliate, mostly in pairs, leallets oval, acuminate; spa- 

 dix clavate; spothe. ovate, acuminate, fiat and deflected above. — A curious and 

 well known inhabitant of wet woodlands, Can. to Car. W. to the Miss. The 

 stem is a ru^.se, (leshy, subterraneous corm giving oil' radicles in a circle from 

 44* 



