'92 



AUISTOLOCHIACE/E. 



[Epigtnous Exogens. 



Order CCCIII. ARISTOLOCHIACEjE.— Birthworts. 



AristolocLiw, Juts. Gen. (1789) ; R Brown Prodr. 349 ; Endl. Gen. cxiv. ; Horsfield PI. Jav. p. 43.- 

 Fistolochinae and Asarinae, Link Handb. 1. 367. (1829).— Asarineae, Bartl. Ord. Kat. 81. (1«30) 



Diagnosis. — Asaral Exogens, with a 3-6-celled ovary and 00 orndes. 



Herbaceous plants or shrubs, the latter often 

 climbing. Wood without concentric zones and 

 inseparable wedges. Leaves alternate, simple, 

 stalked, often with a stipule opposite the leaf, 

 scale-shaped or leafy ; or with none. Flowers 

 axillary, solitary, brown or some dull colour. 

 Flowers hermaphrodite. Calyx adherent, tubu- 

 lar, with the segments valvate or induplicate in 

 aestivation, sometimes regular, sometimes very 

 unequal. Stamens 6 to 12, epigynous, distinct, 

 or adhering to the style and stigmas. Ovary in- 

 ferior, 6-celled, very rarely 3 or 4-celled ; ovules 

 anatropal, 00, horizontally attached to the axis ; 

 style simple ; stigmas radiating, as numerous as 

 the cells of the ovary. Fruit dry or succulent, 

 3- 4- 6-celled, many seeded. Seeds thin, angu- 

 lar, or round, with a very minute embryo placed 

 in the base of fleshy albumen. Cotyledons incon- 

 spicuous ; radicle next the hilum. 



These are usually stationed upon the limits 

 of Endogens and Exogens, agreeing with the 

 former in the ternary division of the flower, 

 and in some respects in habit ; with the latter in 

 the more essential points of their structure. De 

 Candolle, in the Botamicon QaUicwm, places them 

 between Oleasters and Spurge worts, to the former 

 of which he thinks that they approach through 



Fig DXXV. 1 



Asaruin, but with the latter of which 

 their relation is not obvious. To Pas- 

 sionflowera they may be compared, on 

 account of the twining habit, alternate 

 leaves, and leafy stipules of many spe- 

 cies ; and to Cucurbits, on account of 

 their twining habit, and inferior ovary. 

 Brown, however, is of opinion that their 

 affinity is in reality with Nepenths; a 



Fte. nxxv. 



3. half its seed. 



Aristo'.ochia galeata. — Marlins. J. fruit of an Aristolochia ; 2. cross -section of ;t- 



