520 CONTRIBUTIOlSrS FROM THE NATIONAL HEEBAEIUM. 



inserted, epipetalous; ovary 3-celled, with a thick axis; styles united; stigmas 3; 

 fruit a 3-celled loculicidal capsule; seeds several or solitary in each cell, the coats 

 sometimes mucilaginous. 



KEY TO THE GENERA. 



Calyx not ruptured by the capsule; leaves alternate; 

 seeds with mucilage and spiracles (spirally 

 twisted threads) when wetted. 

 Calyx teeth spinulose-tipped ; leaves pinna tifid 

 with linear segments; flowers blue, in few- 

 flowered woolly heads 1. Eeiastrum (p. 520). 



Calyx teeth herbaceous, not spinulose-tipped; 

 leaves and flowers various. 

 Leaves simple, entire; flowers small, capitate- 

 crowded; stamens straight 2. Collomia (p. 521). 



Leaves pinna tifid; flowers large, variously 



arranged; stamens declined 3. Polemonium (p. 521). 



Calyx at length ruptiired by the maturing capsule; 



leaves alternate or opposite; seeds with or 



withoiit mucilage and spiracles when wet. 



Calyx tube not at all or but slightly scarious, 



early splitting; leaves sessile, divided into 



several linear spinulose segments; seeds 



without mucilage and spiracles; plants 



strongly scented 4. Leptodactylon (p. 522). 



Calyx tube more or less scarious between the 



lobes, distended, then ruptured by the 



capsule; leaves sessile or petiolate; seeds 



with or without mucilage when wet. 



Corolla salverform, with a very narrow throat. 



Seeds mucilaginous when wetted ; annual 



with alternate floral leaves 5. Microsteris (p. 523). 



Seeds not altered when wetted; per- 

 ennials with all the leaves oppo- 

 site 6. Phlox (p. 523). 



Corolla funnel form or tubular, with an open 

 throat. 

 Leaves alternate; inflorescence panicu- 

 late, thyrsiform, or capitate 7. Gilia (p. 525). 



Leaves opposite, spinulose-tipped; in- 

 florescence various. 

 Flowers bluish, sessile; leaves with a 

 few narrow unequal segments 



or simple : 8. Linanthus (p. 529). 



Flowers bright yellow, long-pedicel- 

 ed; leaves with several nearly 

 equal segments appearing as 

 a verticel of linear leaves 9. Dactylophyllum (p. 529). 



1. ERIASTBTJM Woot. & Standi. 



Low, wiry-stemmed, widely spreading annual, at first white-woolly throughout, 

 the stems and lower leaves later glabrate; leaves alternate, sessile; flowers small, 

 blue or white, in few-flowered glomerate heads surrounded by several crowded woolly 



