v.fc 



A CONTRIBUTION 



TO OUK 



KNOWLEDGE OF SEEDLINGS 



BEGONIACE.E. 



Benth. et Hook. Gen. PZ. i. 841. 



Fruit and Seed. The ovary of the Begoniaceae is as a rule 

 wholly inferior. That of Hillebrandia forms an exception, 

 being free for a short distance at the apex. Most frequently 

 it is three-celled with three wings or angles, rarely one-, two-, 

 four-, or many-celled. The placentas are axile and simple, 

 or consist of two plates, or are branched and project into 

 the cavity of the ovary ; in the case of one-celled ovaries they 

 are thick and spongy. The ovules are very numerous, most 

 often covering the whole surface of the placentas and ana- 

 tropous. The fruit is capsular, dehiscing loculicidally or rarely 

 septicidally ; but a few species of Begonia have baccate fruits 

 bursting irregularly. Those of Hillebrandia dehisce by a 

 large opening between the styles and above the calyx- 

 segments. The capsule of this genus also differs from the 

 prevailing type by being hemispherical and wingless. The 

 mature fruit has the same number of cells as the ovary, 

 and contains very numerous minute seeds of an oblong 

 or cylindrical outline, with a membranous reticulate testa. 

 Endosperm is wanting, or is reduced to a thin layer sur- 

 rounding the embryo. The latter conforms to the outline of 

 the seed, and has very short cotyledons, with an elongated 



II. B 



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