SUBDIVISION SECOND. 



ENDOGENS, OR MONOCOTYLEDONOUS PLANTS. 



Stem not distinguisliable into bark, pitli 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 Avith 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. E.mkryo with one cotyledon, rarely with two, the second 

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



CliASS III. AGIiUMACEOUS 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. 



Herbs or tropical s>inibs, with a fleshs' rhizoma or cormug. 



Lvs. sheatliiiig at bjise, oflen with branching veins, and sometimes compound. 



Fls. mostly monfBcious and achlamydeous, arranged upon a naked or spathaceous spadiz. 



Perianth, when present, consisting of 4— fi parts. 



Sta. definite or indefinite, hypogynous, very short. Ant?i. ovate, e.vtrorse. 



Ova. free, l— several-celled. Stig-ma s^essile. 



FY.— Berry 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 palustria, 

 extending to the northern frigid zone. . 



Properties.— All acrid, volatile principle pervades the order, which is, in some instances, so concen- 

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

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

 ConspcctiLS of the Genera. 



t Berry 1-seeded. . Peltandra. 2 



( and covered < cylindric. ( Berry many-seeded. Catfa. 3 



< with flowers, i oval, preceding the leaves. . Symplocarpus. 6 



5 Spadix in a spathe ( and naked above. Stem a corm. . . . Arum. l 



J broad. <Spadix naked, yellov/, on a clavate scape. Orontium. 4 



leaves Oinear-ensiform. Scape leaf-like. Spadix lateral. .*.... Acorus. 5 



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. — %. 

 "SC A. TRiPHYLLUM. Dras^oii-Root. Jack-iv-lhe-Pulpit. 

 /Xsaulescent ; Irs. trifoliate, mostly in pair.s, leaflets oval, acuminate ; spa- 

 dix clavate; spathe ovate, acuminate, flat and deflected above. — A cnrioiis and 

 well kno-mi inhabitant of wet -woodlands. Can. to Car. W. to the Miss. The 

 stem is a ru£:ose, fleshy, subterraneous corm giving off radicles in a circle from 

 44* 



