536 ZYGOPHYLLACEAE (;CALTROP FAMILY) 



10. G. MOLLE L. Weak, spreading, soft-pubescent; leaves orbicular, cleft 

 to the middle, the segments crenate or incised ; sepals ovate-oblong, not awned^ 

 villous ; petals rose-colored, notched ; stamens 10 ; carpels transversely wrinkled, 

 glabrous. — Recently seeded lawns, etc., casual but not rare. (Adv. from Eu.) 



11. G. coLUMBiNUM L. (LoNG-sTALKED C.) Minutely hairy, with slender 

 decumbent stems; leaves 5-7-parted, and cut into narrow linear lobes; pedun- 

 cles and pedicels filiform, much elongated ; sepals awned, about equaling the 

 retuse purple petals ; carpels subglabrous ; seeds minutely reticulated. — Borders 

 of fields, etc., N. J. and Pa. to Va. ; also Dak. (Nat. from Eu.) 



2. ER6dIUM L'H6r. Storksbill , 



The 6 shorter stamens sterile or wanting. Styles in fruit twisting spirally, 

 bearded inside. Otherwise as Geranium. (Name from epw8i6s, a heron.) 



1. E. cicutAkium (L.) L'Her. Annual, hairy; stems low, spreading; 

 stipules acute ; leaves pinnate, the leaflets sessile, 1-2-pinnatifid ; sepals bristle- 

 tipped ; filaments not toothed. — About cities, not rare. (Adv. from Eu.) 



2. E. MOscHATUM (L.) L'Her. Similar, but stouter; leaflets less divided; 

 sepals not bristle-tipped; antheriferous filaments 2-toothed. — WsiSte ground, 

 etc., eastw., infrequent. (Adv. from Eu.) 



ZYGOPHYLLACEAE (Caltrop Family) 



Herbs (or southward woody plants), with opposite (or alternate) in our spe- 

 cies abruptly pinnate undotted leaves, andperfect regular mostly b-merous flowers. 

 Stamens free, essentially hypogynous, in ours twice as many as the petals. Pistil 

 of several united 1-feiv-ovuled carpels. Ovules anatropous with superior micro- 

 pyle and large straightish embryo. — Chi-efly tropicaL 



1. Tribulus. Carpels 5, several-ovuled, prickly. 



?/. KallStroemia. Carpels 10, one-ovuled, tubereulate. 



1. TRIBULUS [Tourn.] L. 



Sepals and petals (4-) 5. Filaments slender, unappendaged ; those before the 

 petals sometimes slightly united with them, the alternate ones subtended by 

 glands. Cells of ovary as many as the petals, 3-5-ovuled. — Ours spreading 

 annuals. (The Latin name of the caltrop, which in form its prickly fruit suggests.) 



1. T. TERRESTRis L. (Caltrop.) Brauchcd from the base ; leaflets 5-7 pairs ; 

 flowers small, short-peduncled ; petals pale yellow ; mature carpels crested and 

 armed with 2-4 spreading prickles. — Occasional in Atlantic States; also 111^, 

 Neb., and Kan. ; chiefly on dumps. (Adv. from Old World.) 



2. KALLSTROEMIA Scop. 



Sepals, petals, and stamens as in Tribulus. Cells of the ovary twice as many 

 as the petals, each 1-ovuled, becoming 1-seeded nutlets, dorsally rounded, 

 smooth or tubereulate but not prickly, at maturity falling away from the per- 

 sistent stylar axis. — Diffuse annuals. (Name unexplained, given presumably 

 in honor of some obscure botanist.) 



1. K. MAXIMA (L.) T. & G. Prostrate, grayish-hirsute; leaflets 4-6 pairs, 

 oblong, obtuse, about 1 cm. long ; flowers 9-15 cm. in diameter ; petals yellow ; 

 fruit depressed-ovoid, beaked with a stoutish columnar style. — Railroad yards, 

 etc., w. Mo. and e. Kan., where presumably adventive from the Southwest, 

 (Trop. Am.) 



