280 



lous ovules, and peculiar habit. They are connected with Aroideco by Acorus, 

 which belongs to the latter. Agardh refers Typhacete to glumaceous Mono- 

 cotyledons, on account of the analogy between the calyx of Typha and the 

 hypogynous hairs of Eriophorum, a genus of CyperacefP. They are com- 

 bined with Pandanese by M. Kunth, but appear to be sufficiently distin- 

 guished by the slit in the side of their embryo, their simple fruit, pendulous 

 ovulum, trisepalous calyx, and habit. ' • 



Geography. Found commonly in the ditches and marshes of the 

 northern parts of the world, but uncommon in tropical countries; a species 

 is found in St. Domingo, and another in New Holland. Two are described 

 from equinoctial America. 



Properties. Of little known use'. The powdered flowers have been 

 used as an application to ulcers. The pollen of Typha is inflimmable, like 

 that of Lycopodium, and is used as a substitute for it. M. Decandolle 

 remarks that it is probable the facility of collecting this pollen is the real 

 cause of its use, and that any other kind would do as well. 



Examples. Typha, Sparganium. 



CCLVI. AROIDE^. The Arum Tribe. 



Aroide.t., Jnss. Gen. 23. (178.0); R. Broivn Prodr. 333. (1810); Dec. and Duby, 480. 

 (1828); Lindl. Synops. 246. (1829). — Acorin.e, Link Handb. 1. 144. (1829), a 

 § o/Junceae. 



DiAGXosis. Spadiceous monocotyledons, with simple, succulent, or 

 capsular fruit, a developed spatha, and sub-sessile anthers. 



Anomalies. Albumen sometimes absent. In Tacca the ovarium is 

 inferior. Spatha absent or rudimentary in some. 



Essential Character Flowers unisexual, arranged upon a spadix, frequently 



naked. Perianthium either wanting, or consisting of 4 or G pieces. Males: Stamens 

 definite or indefinite, hypogynous, very short ; anthers 1- 2- or many-celled, ovate, turned 

 outwards. Females: Ovarium superior, 1-celled, very seldom 3-celled, and many-seeded; 

 ovules erect, or pendulous, or parietal ; stigma sessile. Fruit succulent or dry, not opening. 

 Seeds solitary or several ; embryo in the axis of fleshy or mealy albumen, straight, taper, 

 with a clelt in one side, in which the plumula lies; {radicle obtuse, usually next the hilunj, 

 occasionally at the opposite extremity. R. Br.) — Herbaceous plants, frequently with a 

 fleshy cormus, or shrubs ; stemless or arborescent, or climbing by means of aerial roots. 

 Leaves sheathing at the base, either with parallel or branching veins ; sometimes com- 

 pound ! often cordate. Spadix generally enclosed in a spathe. 



Affinities. The Arum tribe may be considered the centre of a system 

 of organisation, of which the other orders of Spadiceoe are rays of unequal 

 length. Taking its "diagnosis as given above, we shall have it specially 

 known by its highly developed spatha; Typhacea; will be distinguished by 

 their long anthers and want of s})atha, Pandaneu; by their arborescent habit 

 and drupaceous compound fruit, Fluviales and Juncagineee by their want of 

 spatha and return from the spadiceous form of inflorescence, and Pistiacese 

 by their reduction to the simplest state in which flowering plants can exist. 

 The whole of these tribes, taken together, are known by their general ten- 

 dency to develope their flowers upon a spadix, by their want of floral enve- 

 lopes, or by those parts not assumiuti:: the distinct forms of calyx and corolla, 

 but existing only in the state of herbaceous scales. With the exception of 

 Pandanepn, they are all also known by their plumula lying within a cleft of 

 the embryo; a structure found in no other monocotyledonous plants, except 

 Grasses, in which the embryo is otherwise widely different. Mr. Brown has 



