FLOWERING PLANTS AND FERNS OF ARIZONA 303 



sometimes apetalous; styles and stigmas 2 to 5; ovary superior; fruit 

 a many-seeded capsule, dehiscent by valves at least at apex, or a 

 1-seeded aehene or utricle. 



This family includes those favorites of gardeners and florists, the 

 pinks and carnations, but in many of the genera the plants are insignif- 

 icant, with small, inconspicuous flowers. 



Key to the genera 



1. Fruit a 1-seeded aehene or utricle, enclosed in the calyx tube; stipules scarious; 

 sepals more or less united; petals minute or none (2). 

 2. Plant perennial, pulvinate-cespitose: stipules large and conspicuous, not or 

 not much shorter than the leaf blades; flowers in terminal cymose 



clusters 9. Paronychia. 



2. Plants annual; stipules relatively small, much shorter than the blades; 

 flowers in axillary clusters (3). 

 3. Sepals with conspicuous thin white blades and green claws, these united 



below into an elongate, turbinate tube 8. Achyroxychia. 



3. Sepals greenish, without differentiation of claw and blade, united only to- 

 ward the base 10. Herxiaria. 



1 Fruit a several-seeded capsule, valvate, at least at apex; petals usually present 



(4). 



4. Sepals united for most of their length, forming a more or less inflated gamo- 



sepalous calyx, this 5-toothed at apex; petals with long claws, usually 



with appendages forming a crown in the throat of the corolla (5). 



5. Calyx terete or 5-angled, inconspicuously veined; petals with or without a 



crown: herbage glabrous or obscurely puberulent 13. Sapoxaria. 



5. Calyx with 10 or more conspicuous longitudinal nerves or ribs; petals 

 with crownlike appendages, these sometimes reduced to small scales 

 (6). 

 6. Styles normally 3; ovary and capsule stipitate or at least narrowed at 



base; blade of the petal broader than the claw 11. Silexe. 



6. Styles 4 or 5: ovary and capsule sessile or very nearly so, broad at base; 

 blade of the petal not or very little wider than the apical part of the 



claw 12. Lychnis. 



4. Sepals separate to the base or nearlv so; petals not clawed or appendaged 

 (7). 

 7. Style one, 3-cleft or 3-toothed; capsule 3-valved (8). 



8. Petals usually present although sometimes very small; sepals not re- 

 curved or rigid 6. Drymaria. 



8. Petals minute or none; sepals recurved, becoming rigid and almost 



spinose 7. Loeflixgia. 



7. Styles 3 to 5, usually separate to the base (9) . 



9. Stipules present, scarious, conspicuous; petals pink, entire, sometimes 



rudimentary 5. Spergularia. 



9. Stipules none; petals white, occasional! v purple tinged, rarelv wanting 

 (10). 

 10. Stvles alternate with the sepals and of the same number, usually 5. 



3. Sagixa. 

 10. Styles opposite the sepals or, if fewer in number, then opposite the 

 outer sepals (11). 

 11. Capsule elongate, cylindric, often curved, dehiscent at apex with 

 twice as many teeth as there are styles: styles usually 5. 



2. Cerastium. 

 11. Capsule short, ovoid or oblong, straight, splitting into as many 

 valves as there are stvles, the valves often 2-cleft: stvles usually 

 3 (12). 



12. Petals bifid, often deeply so, rarely none 1. Stellaria. 



12. Petals entire or slightly emarginate 4. Arexaria. 



1. STELLARIA. Chickweed 



Plants small, herbaceous, annual or perennial, usually with tufted 

 stems; flowers solitary in the axils or in few-flowered terminal cymes, 



2SG744 — 42 20 



