288 70. ARISTOLOCHIACE.E. 



1. THESIUM Linn. 



1 . T. humifusum (DC. ) 5 st. procumbent or ascending racemose, 

 racemes branched or simple, fl.-stalks as long or longer than the 

 fl., fr. -stalks patent, angles of fr.-stalks and edges of bracts and 

 upper 1. denticulate-scabrous, fr. oval-oblong, 1. 1 -veined linear. 

 R. xi. 542. T. linophyllum Sm., E. B. 24/. Parasitical. 

 Root woody. St. nearly always procumbent. L. very slender; 

 veins usually obscure. Middle bract in lower part of racemes 

 exceeding flowers. Tube of perianth very short, open, funnel- 

 shaped ; segm. triangular, spreading, a tooth on each side. Fr. 

 oval, exceeding perianth which is usually inflexed only at the 

 end, strongly ribbed, slightly netted, persistent. Chalky and 

 limestone (oolite) hills. P. VI. VII. E. 



[T. intermedium (Schrad.); st. more erect panicled, panicle 

 pyramidal, lowest branches longest, 1. linear-lanceolate 3-veined ; 

 is said to be a native of Britain, but all the specimens which I 

 have seen belong to T. hvmifusum.~\ 



[2. T. Jiumile (Vahl) ; racemes spiked, fl. nearly sessile, fr. 

 strongly ribbed and netted sessile crowned with the very short 

 inflexed perianth, 1. fleshy linear 1 -veined. R. xi. 542. Fr. 4 

 or 5 times as long as the persistent inflexed perianth. Middle 

 bract much exceeding the flowers. I gathered 2 specimens of 

 this plant somewhere near Dawlish in Devonshire, in 1829, but 

 it was probably not indigenous. P. VII. VIII.] E. 



Order LXX. ARISTOLOCH1ACE.E. 



Perianth adnate to the ovary below, tubular above, with a 

 lobed dilated usually irregular limb. Stain. 6 12, epigynous. 

 Ovary 3 6-celled. Style simple ; stigma radiant. Fr. many- 

 seeded. Seed with a minute embryo at the base of fleshy albu- 

 men. For fig. of genera see G. jP. G. Monochl. 50, 51. 



1. ARISTOLOCHIA. Perianth tubular, swelling at the base; 

 mouth dilated on one side. Anth. 6, adnate to the short 

 columnar style under the 6-lobed stigma. Caps. 6-celled. 



2. ASARUM. Perianth bellshaped, 3-fid. Stam. 12, inserted 

 at the base of the style. Anth. attached to the middle of 

 the filaments. Stigma 6-lobed. Caps. 6-celled. 



1. ARISTOLOCHIA Linn. Birthwort. 



*1. A. Clematitis (L.) ; root creeping, st. erect simple, 1. cor- 

 date stalked glabrous, fl. aggregate. E. E. 398. St. 6. 16. Fl. 

 pale yellow. Naturalized near old ruins. P. VII. VIII. E. 



