304 



XLV. ZYGOPHYLLE^. 



-• THbul-us. 

 Flower (mag.). 



Ti'ibuUis terrestris. 



Trihulus. 

 Vertical section of flower (mag.). 



Calyx 4-5-merows, generally imbricate. Petals hypogynous, usually imbricate. 

 Stamens usually double the number of the petals, hypogynous ; filaments usually with a 

 scale inside. Otakt several-celled. Fruit a loculicidal capsule, septicidally dividing 

 into cocci. Embeto exalbuminous, or enclosed in a cartilaginous albumen. — Scentless 

 plants. Leaves opposite, pinnate, stipulate. 



Herbs, shrubs or trees ; branches often divaricate and jointed at the nodes. 

 Leaves opposite, or alternate from the suppression of one, stipulate, compound, 

 sometimes pinnate or imparipinnate, sometimes 2- (rarely 1-) foliolate {Zygophyllum) ; 

 petiole sometimes flattened and winged; leaflets sessile, entire, not punctate, often 

 inequilateral, flat, or fleshy, or terete ; stipules geminate at the base of the petioles, 

 persistent, sometimes spinescent. Elcwees 5 , regular or irregular, white, red or 

 yellow, rarely blue ; peduncles usually 1-2, springing from the axil of the stipules, 

 1-flowered, ebracteate. Sepals 5-4, usually persistent, free, rarely connate at the 

 base, Eestivation imbricate or very rarely valvate {Seetzenia). Petals 6-4, very rarely 

 [Seetzenia), hypogynous, free, Eestivation usually imbricate, sometimes contorted 

 {Zygophyllum) ; dish hypogynous, convex or depressed, rarely annular (Trihulus), 

 sometimes inconspicuous {Fagonia, Guaiacum, &c.), or (Seetzenia). Stamens 

 usually double the number of the petals, rarely equal (Seetzenia), inserted on the re- 

 ceptacle, 2-seriate, the outer opposite to the sepals ; filaments filiform, usually with 

 a small scale on the base within, or on their centre ; anthers introrse, dorsifixed 

 above their base, versatile, dehiscence longitudinal. Ovart free, sessile, or rarely 

 borne on a short gynophore (Larrea, Guaiacum), furrowed, angular, or winged, 4-5- 

 ^arely 10-12-) celled (Trihulus, Augea), or 2-3-celled (Zygophyllum), cells sometimes 



