PETALOIDEJE. 383 



adapted for the microscopic investigation of living tissues. Ekdea cana- 

 densis is the American Water-weed, which has increased so rapidly in our 

 canals and ditches since its introduction from America some years since. 



Distribution. The species are not numerous ; they are found in fresh 

 water in Europe, N. America, E. Indies, and New Holland. 



Qnaiities nnd Uses. They appear to have no very active properties. 

 Hydrocharis is said to be astringent. 



Series 2. 

 Flower-tube free from the ovary. 



A. SYNCARPIJE. 



Carpels united ; seed usually perispermic. 



PHILESTACE^E are climbing or erect shrubs with coriaceous, netted- 

 ribbed leaves and large and showy perfect flowers with a C-merous peri- 

 anth in two circles, equal, or the calyx much shorter ; stamens 6, adherent 

 to the perianth at the base ; ovary 1-celled, with 3 parietal placentas ; 

 ovules semianatropous (not orthotropous, as is commonly stated). These 

 plants, consisting of Lcmageria rosea, a climbing shrub with beautiful 

 crimson flowers and basifixed anthers, and Phiksia buxifolia, the flowers 

 of which differ chiefly in the marked difference of calycine and corolline 

 circles and the mode of union of the bases of the filaments and versatile 

 anthers, differ from Liliaceae chiefly in the parietal position of the pla- 

 centas ; in habit Lapayeria is related to Smilax, and is in some measure 

 intermediate between Smilaceae and Liliaceae. They are Chilian plants, 

 now in cultivation with us. Lapageria bears sweet edible berries. 



ROXBUKGHIACEyE consist of 4 species of Roxlurrjfiia, twining 

 shrubs with broad leathery leaves and tuberous roots, from the hotter 

 parts of the East Indies. Their habit connects them with Smilaceae ; but 

 their perianth is composed of 4 petaloid pieces, and they have 4 stamens 

 with enlarged connectives (each set of organs, according to Griffith, in 2 

 dimerous circles), and the 1-celled ovary (formed of 1 carpel, according to 

 Griffith) has numerous anatropous ovules arising from the base of the 

 cavity ; the sessile stigma is penicillate. The fruit is 2-valved, with 2 

 clusters of seeds attached on long cords; embryo in the axis of fleshy 

 perisperm. The affinities of these plants are not clear ; but the resem- 

 blance is perhaps greater to Paris than to any other genus that can 

 be named. 



SMILACE^E (THE SARSAPARILLA ORDER) consists of herbs or climb- 

 ing shrubby plants with stalked netted-veined leaves, regular perfect or 

 dioecious flowers, with the 6-10-parted perianth of the fertile flowers free 

 from the 3-5- (rarely 1-2-) celled ovary ; stamens 6-10, introrse ; anthers 

 adnate, basifixed ; styles or sessile stigmas as many as the cells of the 

 ovary, and distinct ; fruit baccate, with few or several seeds ; ovules ortho- 



