38 CONTKIBUTIONS FKOM THE NATIONAL HERBARIUM. 



K. 



Plants with leafy steins; leaves alternate, the blades simple, entire, net-veined. 



Stem leaves reduced to minute scales. Corolla very irregular, spurred; small slender 



plants of very wet soil PINGUICTJLACEAE (p. 255). 



Stemjleaves not reduced to scales. 



Leaves with stipules, these sometimes united into a sheath. 



Stipules united and sheathing; fruit an achene. Petals none, the flowers small, 



greenish, whitish, or pink, mostly axillary or in spikes. 



POLYGONACEAE (p. 144). 



Stipules not sheathing; fruit a capsule or a pod, with more than one seed. 



Petals none; plants glabrous; fruit a small 3-celled capsule. 



PhyUanthus (p. 195). 



Petals present, yellow; plants pubescent; fruit an inflated 1-celled pod. 



Crotalaria (p. 183). 

 Leaves without stipules. 



Corolla gamopetalous, usually colored and conspicuous. 



Flowers 4-5 cm. long, white; calyx inclosed by 2 broad bracts. Leaves often 



cordate at the base; fruit a capsule Convolvulus (p. 234). 



Flowers less than 3 cm. long; calyx not inclosed by 2 broad bracts. 



Juice milky; flowers in umbels; fruit of 1 or 2 large pods, the seeds with 



tufts of hairs Acerates (p. 231). 



Juice colorless; flowers not in umbels; fruit a small capsule or beiry or of 4 



nutlets, the seeds not with tufts of hairs. 



Corolla spurred, yellow. Nearly glal)rous, glaucous perennial. 



Linaria (p. 250). 

 Corolla not spurred. 

 Fruit of 4 nutlets; plants rough-hairj^, often bristly, or glabrous and with 

 blue flowers (the flowers sometimes white, yellow, or reddish). 



BORAGINACEAE (p. 237)- 

 Fruit a capsule or a berry; plants never rough-hairy, not mth blue 

 flowers. 

 Corolla white; fruit a capsule; calyx not enlarged in fruit. 



PEIMTJLACEAE (p. 225). 

 Corolla yellow; fruit a berry, inclosed by the enlarged bladdery calyx. 



Physalis (p. 247). 

 Corolla of distinct petals or wanting, the calyx sometimes colored and corolla-like. 

 Flowers with neither calyx nor corolla, crowded in long cylindrical dense 

 spikes; leaves cordate, petioled. Plants of marshy soil. 



SAURURACEAE (p. 132). 



Flowers with a calyx and often with a corolla; leaves not cordate, or, if so, the 



flowers not in spikes. 



Flowers green, small, the sepals never colored; petals none. Fruit dry or 



nearly so. 



Plants perennial, pubescent; fruit a capsule, with more than 1 seed. Leaves 



small and narrow CISTACEAE (p. 205). 



Plants annual, glabrous or pubescent; fruit an achene or a l-seeded capsule. 

 Flowers all in loose cymose axillary clusters; style 1, not branched. 



Plants pubescent Parietaria (p. 142). 



li lowers all or most of them in spikes or terminal cymes or panicles, or 



else all in dense sessile axillary clusters; styles 2 or 3, or 1 and 



branched. 



Flowers subtended by scarious bracta, the sepals awn-pointed; fruit 



dehiscent or indehiscent; leaves never linear nor with spiny tips; 



plants never white-mealy AMARANTH ACEAE (p. 148). 



