RUTACE A. 425 
the petals are totally wanting. Thus defined, the genus of Zygophy!- 
lum comprehends some fifty species! Only one belongs to America, 
the greater number growing in Australia, South Africa, and the East. 
Beside Zygophyllum are ranged: Fagonia (figs. 504, 505), whose 
pentamerous flowers have naked staminal filaments, a sessile ovary, 
with two ovules inserted quite close to the base of the internal 
Fagonia cretica. 

Fra. 504. 
Flower (2). 
Fra. 505. 
Long. sect. of flower (8). 
angle of each cell, fruit with five monospermous shells the endocarp 
separating from the exocarp at maturity, and ramified herbaceous 
stems, with opposite leaves 1—3-foliolate; Seefzenia, having apeta- 
lous, isostemonous flowers; most authors also place in this group 
the genera Peganum and Tribulus. 
Peganun® (figs. 506-510) has regular hermaphrodite flowers, of 
quaternary or quinary type. In the latter case, the convex recep- 
tacle supports five sepals, open, valvate, or slightly imbricated in 
præfloration, similar to leaves, some entire, others unequally dentate, 
or pinnatifid. The alternate petals, the same in number, are free 
and imbricated or contorted in the bud. ‘The stamens are three 
times as numerous,’ free, either all fertile, with two-celled, introrse 

1 Dewess., Ic, Sel., iti. t. 42 (Ræpera).— fig. 8.—Spracu, Suit. à Buffon, ii. 314. — 
Lxpes., Ic. Fl. Alt., t. 102, 140, 218, 273, 
382, 383. — WEBB, Phyt. Canar., t. 1.—F. 
Muezz., Fl. Vict., i. 100, t. 6.—BENTH., F4, 
Austral., i, 292.—Hary. & Sonn., Fl. Cap., i. 
355.—Otiv., Fl. Trop. Afr., i. 285.—Borss., 
Fl, Or, i. 909, 916 (Miltianthus).—Watp., 
Rep., i. 494; ii, 823; v. 385 (Sarcozygium), 
386; Ann., i. 150; ii. 245; iv. 404; vii. 479, 
481 (Ræœpera). 
ane Gene ne 601 JS Gen, 0297. — 
GÆRIN., Fruct., ii. 87, t. 95.—Lamx., Dict., iii. 
76; Suppl. iii. 6; Z., t. 401.—DC., Prodr., i. 
712.—A, Juss., in Mém. Mus., xii. 461, t. 16, 
Enpu., Gen. n. 6025.—Payer, Organog., 69, 
t. 14.—AG., Theor. Syst., t. 18, figs. 16, 17.— 
B. H., Gen., 287, n.12.—H. Bn., in Adansonia, 
x. 299.—Harmala T., Inst, 257, t. 133. — 
Maneu, Meth., 239. 
% According to PAYER, five are alternipe- 
talous; aud the ten others, representing the 
five oppositipetalous pieces of the androceum 
lined (congenitally without doubt), are super- 
posed by pairs to the petals. The pollen is, 
according to Moun (in Ann. Se. Nat., sér. 2, 
ili, 339), similar to that of Ruta. 
