POLEMONIACEJS. (POLEMONIUM FAMILY.) 249 



A. Stamens usually unequally inserted: leaves mostly alternate, and pinnalely 

 incised or divided: seed-coat usually developing spiral threads when wetted. 



* Leaves sessile and entire : ovules solitary : more or less viscid-pubescent or 

 glandular plants, 



1. G. linearis, Gray. Branching and in age spreading, a span or two 

 high : flowers capitate-crowded and leaf y-br acted : calyx obconical; its lobes tri- 

 angular-lanceolate : corolla from lilac-purple to nearly white, very slender. 

 Proc. Am. Acad. xvii. 223. Collomia linearis, Nutt. From Colorado and 

 California northward throughout British America. 



2. G. gracilis, Hook. At length corymbosely much branched and 

 spreading, 2 to 6 inches high : leaves lanceolate or linear or the lowest oval 

 or obovate : flowers rather loosely cymose or scattered : calyx rounded at base ; 

 its lobes subulate-linear : corolla purple or violet ; its narrow tube yellowish : 

 the mucilage-cells of the seed-coat wholly destitute of spiracles ! Collomia gra- 

 cilis, Dougl. From Arizona and New Mexico northward through Colorado to 

 British Columbia. 



* * Cauline leaves very numerous, simply pinnately parted into narrowly linear 



divisions: inflorescence thyrsiform or panicled : ovules numerous in each cell: 

 slightly if at all viscid plants. 



3. G. longiflora, Don. Glabrous, loosely paniculate-branched : divisions 

 of the leaves long and slender: flowers somewhat corymbose- on slender pedun- 

 cles: corolla white, strictly salverform, showy; the tube often 1^- inches long, 

 with narrow orifice ; lobes orbicular or ovate. Collomia longiflora, Gray. W. 

 Nebraska and Colorado to Texas and Arizona. 



4. G. aggregata, Spreng. Somewhat pubescent: stems 2 to 4 feet high, 

 leafy, sometimes loosely branching : leaves thickish, with narrowly linear 

 mucrouulate divisions : thi/rsoid narrow panicle loose or interrupted ; the flowers 

 sessile in small mostly short-pedunculate clusters : calyx commonly glandular : 

 corolla from scarlet to pink-red (rarely white), with narrow tube; the lobes ovate 

 or lanceolate, acute or acuminate, widely spreading, soon recurved. Collomia 

 aggregata, Porter. From W. Nebraska to Oregon, and southward to Cali- 

 fornia, New Mexico, and W. Texas. 



Var. attenuata, Gray. Corolla-lobes lanceolate, tapering gradually from 

 the very base into a slender acumination : calyx-lobes equally slender. Synopt. 

 Fl. ii. 145. Middle Park, Colorado. 



K. Stamens equally inserted : seed-coat sometimes developing spiral threads. 



* Leaves either opposite or palmately divided, or both ; their divisions from na.r- 



rowly linear to filiform. 

 - Leaves opposite : flowers small, in a head or dense cluster. 



5. G. nudicaulis, Gray. Very glabrous, an inch to a span high, at 

 length branching from the base : stem leafless from the cotyledons up to the 

 inflorescence, which is a close head or glomerule subtended by an involucre 

 of several entire ovate-lanceolate or lanceolate foliaceous bracts : corolla salver- 

 form, white, pink, or yellow ; tlie tube 3 or 4 lines long and thrice the length 

 of the calyx: ovules 10 to 16 in each cell. Proc. Am. Acad. viii. 266. Sandy 

 plains, from Colorado to Nevada and Oregon. In spring. 



