XCI. CALLITRICHINE^E. 417 



STEM herbaceous. LEAVES all radical, petiole long, blade usually reniform, 

 crenulate, hairy. FLOWERS $ , or imperfect, monoecious or dioecious, ebracteate ; 

 scape bearing a very close spike, composed of several spikelets, each furnished with a 

 bract. PERIANTH 4-partite, 2 segments small, tooth-shaped, alternating with 2 

 larger, petaloid, caducous, sometimes obsolete, reduced to scales in the $ flowers. 

 [Perianth otherwise described as, CALYX-LOBES 2-3, equal or unequal, or 0. PETALS 

 or 2, hooded.] STAMENS 2, opposite to the petaloid segments ; filaments short [or 

 long] ; anthers 2- celled, [basifixed], dehiscence longitudinal [lateral]. OVARY in- 

 ferior, 1 -celled ; styles 2, covered with stigmatic papilla) ; ovule solitary, pendulous 

 from the top of the cell. FRUIT a drupe. EMBRYO minute, at the top of a fleshy 

 albumen ; radicle superior. 



GENUS. 

 * Gunnera. 



A. de Jussieu considered that, in many cases, apetalous and diclinous structures were to be regarded 

 as arrested conditions of perfect types, which masked affinities without annulling them; and this 

 explains the position he gives to Gunneracece, between Araliacece and Cornea, which they approach in 

 their flower, which is hermaphrodite in some species, in their epigyny, the single pendulous anatropous 

 ovule in each carpel, the drupaceous fxuit, and the minute embryo at the top of a fleshy albumen. The 

 same considerations establish the affinity of Gunneracete with Haloragcce ; in both these families may be 

 observed, on the one hand, a perfect organization ; on the other, the absence of petals, and the abortion 

 of the reproductive organs ; and the analogy is increased by the stigmatic papillae along the styles. 



The few species of this little group inhabit tropical Southern Africa and America, the high mountains 

 of tropical America, the Sandwich and Society Islands, Java, [Australia] and New Zealand. 



The fruit of Gunnera macrophy lla is used in Java as a stimulant. The roots of G. scabra, called 

 Panque in Chili, and cultivated in Europe for the beauty of its leaves, which are sometimes more than 

 six feet in diameter, contain astringent principles, and are used in Chili for tanning skins, and as 

 an anti-dvsenteric. 



XCI. CALLITRICIUNE^, LtveilU. 1 



Floating flaccid annual HERBS, simple or branched, stem cylindric. LEAVES 

 opposite, sessile, the lower [submerged], often linear, the upper oval, 1-3-nerved, 

 entire, emerged, often rosulate ; stipules 0. FLOWERS $ or monoecious-dioecious 

 by arrest, solitary and sessile in the axil of the leaves ; involucre diphyllous [or 0] , 

 of 2 lateral opposite curved somewhat fleshy and coloured [white] persistent or 

 deciduous leaflets. PERIANTH 0. STAMEN posterior, rarely 2 antero-posterior, 

 inserted below the ovary in the $ flowers ; filament filiform, elongated ; anther 

 reniform, basifixed, 1-celled, opening at the top by an arched slit. OVARY free, at 

 first sessile, then stipitate, formed of 2 bilobed carpels with two 2-ovuled cells ; 2 

 styles 2, distant ; stigmas acute, papillose over the whole surface ; ovules curved, fixed 

 to the central angle near the top of the cell ; micropyle lateral and internal, placed 



1 See under Haloragea, p. 414. ED. cells, but considered as originally 2-celled, each cell being 



2 The ovary is 4-lcbed and 4-celled with 1-ovuled divided into two by the inflection of its -walls. ED. 



E E 



