DILLENIACE2E. 



91 



with the sepals, and of a somewhat variably imbricated aestivation ; 

 an aiidroceum of a large number of stamens arranged, when at 

 maturity/ without any apparent order below the gynseceum, and 

 each formed of a filament free for almost its whole length, and a 



Fig. j29. 

 Diagram. 



C'^^S.^.V 



Hihberiia volubilis. 



Fig, 130. 

 Longitudinal section of flower. 



basifixed, two-celled, introrse anther dehiscing by two longitudinal 

 clefts.^ These stamens are shorter, as they are more external ; and 

 some of them, quite outside the rest, are even reduced to short sterile 

 rods. The gynseceum most usually consists of five^ free carpels super- 

 posed to the petals, each consisting of a one-celled ovary, surmounted 

 by a style, dilated and stigmatiferous at the tip. In the internal 

 angle of the ovary is seen the placenta, which bears about half-a- 

 dozen^ anatropous, ascending ovules, of which the raphes tend 

 to be adjacent. The thickened funicle is early dilated around the 

 hilum to form the commencement of an aril.^ The fruit is multiple, 

 consisting of dry carpels, like those of CandoUca, each containing one 

 or more seeds, possessing a membranous aril more or less laciniate 

 at the margin. H. volubilis is a sarmentose shrub, with alternate 



^ We shall see that at an earlier period they 

 are united into five bundles, of variable form, 

 alternate with the petals. The anthers may be 

 of the same form as in Candollea (fig. 120). 



' The whitish pollen grains have each three 

 equidistant longitudinal grooves. 



^ This species is one of those in which two 

 whorls of carpels are pretty often found, of which 

 the internal one consists of alternipetalous ele- 

 ments, and may be complete or incomplete. 

 More rarely the carpels exceed ten in number. 

 TuEPiN has given a very exact figure of a plant 

 with a gynseceum of eight carpels {Did. des 

 Set. Nat., t. 116); we rarely meet with less than 

 five. 



•* This number varies; but most usually we 

 find five or six ovules 'in two vertical rows; they 

 are ascending, but at the same time turn towards 

 one another, so that the raphes nearly touch. 

 They have two coats, and the youngest are 

 highest up on the placenta. 



* It is a fair time before anthesis that the 

 aril appears as a small ring, and afterwards as a 

 cup with an entire rim. By the unequal de- 

 velopment, this rim is more or less raised at 

 various points— the origin of the deep lobiug 

 observed iu the aril at a later period. The cells 

 composing it are elongated and translucent, with 

 thin, brittle walls. 



