FLOWERING PLANT.- AND FERNS OF ARIZONA 861 



1. Fruit not gourdlike or hard-shelled, at maturity not more than 3 cm. in diam- 

 eter; stems climbing, with long, filiform, many-coiled tendrils; fl< 

 monoecious 'except in TberviUea ; corolla whitish or pale yellow 3 . 

 3. Hypanthiurn (at least in the pistillate flow a and narrowly cylindric; 



fruits globose, berrylike, smooth, several-seeded 4 . 

 4. Thickened root single; flowers dioecious, the staminate ones with a 

 campanulate hypanthiurn; seeds rounded at the large end. 



2. Ibervillea. 



4. Thickened toot- I, often forked; flowers monoecious, ninate 



ones with a long, slender-cylindric hypanthiurn; seeds truncate at the 



lars:e end 3. Tumamoca. 



3. Hypanthiurn short-campanulaTe or, if elon^ate-cylindric (in the pistillate 

 flowers of genus Brandegea), then the fruit asymmetric, long-beaked, 1- 

 celled and 1-- ceded; fruits not globose and berrylike or, if so, then spiny; 

 corolla of the staminate flowers rotate, whitish 5 . 



5. Ovule and seed solitary; ovary 1-celled; corolla of the staminate flowers 



not more than 6 nun. in dia: 

 Fruit very asymmetric, narrowly obovoid, with a long slender beak; 



plant perennial 8. Braxdegea. 



6. Fruit symmetric or nearly so, ovoid, not long-beaked; plants annual I 7 . 

 7. Pistillate flowers in short-stalked, subcapitate or subumbellate clus- 

 ter.-, not hidden by the bracts; fruit spiny; corolla lobes not bi- 



cuspidate 9. Sictos. 



7. Pistillate flowers solitary or in pairs in the leaf axils, each enveloped 

 and hidden by an infolded, leaflike, 3-lobed and dentate bract; 



fruit smooth; corolla lobes bicuspidate 10. Sicyosperma. 



5. Ovules aid seeds several, on 3 or more placentas; fruit spiny; pistillate 

 flowers solitary (8). 

 8. Anthers completely fused and appearing as a horizontal ring opening all 

 around; leaf blade- pedately parted or divided- _ 11. Cyclaxthera. 

 8. Anthers evidently more than one, opening longitudinally; leaf blades 

 not parted or divided, but sometimes deeply cleft 9 . 

 9. Plant perennial; fruit globose; seed- round and turgid. . 7. Marah. 

 9. Plants annual; fruit ovoid; seeds flat (10 . 



10. Fruit regularly dehiscent (operculate), the acuminate apical 

 portion coining away as a lid, the spines glandular-hirsute. 



5. Echixopepox. 



10. Fruit bur-ting: irregularly at the rounded apex not op I . 



the spine- not hirsute 6. Echinocystis. 



1. APODAXTHERA. Melox-loco 



Plant perennial, coarse, with a large thick root, the herbage harshly 



appressed-puboscent : flowers few. unisexual (monoecious, : calyx with 

 the tube Tiypanthiumj l.o to 2.5 cm. long and tin- teeth subulate; 

 corolla yellow, the lobes separate or very nearly so: stamens 3. one 

 with a 1 -celled anther and two with the anthers 2-celled, the anthers 

 separate, sessile; fruit oval, longitudinally ridged. 



1. Apodanthera undulata A. Gray. PL Wright. 2: 60. 18£ 



Pinal, Cochise. Santa Cruz, and Pima Counties, 1.500 to 5.500 feet, 

 dry plains and mesas, sometimes on limestone slopes. June to Septem- 

 ber. Western Texas to southern Arizona and Mexico. 



The plant has a disagreeable odor. 



2. IBERVILLEA 



Plant perennial, glabrous or nearly so: stems slender, from a thick 

 nearly globose mot; leaves pedately parted or divided: flowers -mall. 



dioecious, the staminate one- in short racemes or corymbs, the pistillate 

 flowers solitary, axillary; fruit a red globose berry. 



