Alismales.] ALISMALES. 207 



Alliance XVII. ALISMALES.— Tim Alismal Alliance. 



Diagnosis. — Hyporjunous, (bisexual), trl-hcxapetaloideoii^ Endogens, with separate 

 carpels and no albumen. 



These stand in the same relation to hermaphrodite hypogynous Endogens as Orchi- 

 dals and Hydrals to the Alliances with which they are respectively associated. The want 

 of albumen is their gi-eat feature. They are however known, in addition, by their car- 

 pels not ha^^ng any tendency to combme ; so that they are to Endogens ahnost what 

 the Crowfoots are to Exogens. And it is to be observed that if it were not for their 

 monocotyledonous embryo there would be no distinguishing such plants as AUsma from 

 certain Ranuncuh, represented by Ranunculus parnassifolius. A very few are (^ ? ; 

 such however occur only among the AUsmads, and are not liable to be mistaken for any 

 other plants than Hydrals, with none of the Orders in which can they be properly asso- 

 ciated. Arrow-grasses offer the loAvest organization in the Order, and may be regarded 

 as an Alismal form of Naiads. 



This Alliance seems to close the class of Endogens, and to stand on the Umits of 

 Exogens, in consequence of the intimate and unquestionable relation between Ahsraads 

 and Crowfoots. 



Natural Orders of Alismals. 



Floivers S-petaMdeous. Placentee many-seeded, netted and'} ^^^ Butomace,e. 



parietal J 



Floivers Z-petaloideous. PlacentcB few-seeded, simple, and \ ^ .^ Alismace.e. 



axile, or basal. Embryo solid J 



Flowers scaly. Placent£efeiv-seeded,simple and axile,or basal, \ ^^ Juncaginace^. 



slit on one side, with a very large phimtda 



