Most of our plants belong to the var. ligulatus Shinners in which the ligules 

 are several mm. long, surpassing the disk corollas and the pappus; these plants 

 have long passed under the dubious name A. exilis Ell. It is an abundant weed 

 in ditches, swales, margins of ponds, lakes and streams and poorly drained places 

 in general, throughout our area, probably our most abundant Aster, summer-fall; 

 widespread in the warmer parts of Am., n. to S.C., Mo., Kan., N.M., Ariz, and 

 Calif. The var. euroauster Fern. & Grisc, characterized by its much-reduced to 

 essentially nonexistent ligules, is extremely rare in s.e. Tex. (Orange Co.) where 

 it grows about and in ponds, Aug.-Sept. It occurs from Conn, to Fla., w. to 

 Tex. One old Galveston collection is referable to the var. australis Shinners, in 

 which the ligules are about equal to the disk corollas and to the pappus in length. 

 It is widespread in C.A. and S.A. The var. subulatus is very near the coast from 

 Me. to La. 



It has been suggested that A. spinosus, A. subulatus and A. tenuif alius should 

 be segregated as a genus. They do form a coherent natural group somewhat 

 different from our other Asters. 



4. Aster intiicatus (Gray) Blake. Shrubby alkali aster. 



Shrubby perennial; stems 0.6-0.8 m. tall, rigidly and intricately branched, 

 glaucescent and essentially glabrous throughout; leaves linear, 1-2 cm. long, 

 1-2 mm. wide, entire, mucronulate, fleshy, those of inflorescence reduced, mostly 

 appressed, scalelike, 1-4 mm. long; heads solitary at tips of branches, discoid, 

 5-8 mm. wide, 8-10 mm. high; involucre turbinate-campanulate, 6-7 mm. high, 

 about 5-seriate; phyllaries strongly graduated, appressed, linear or lanceolate- 

 linear, acute or acuminate, the outer phyllaries cuspidulate, glabrous or obscurely 

 ciliolate, chartaceous, whitish, with green midline; corollas usually yellowish; 

 achenes terete, many-ribbed, appressed-pilose; style appendages lanceolate-subulate, 

 longer than the stigmatic region. 



Alkaline meadows, in moist or wet soils, in Ariz. (Mohave, Maricopa, Pinal, 

 Cochise and Pima cos.), May-Oct.; also Nev. and Calif. 



5. Aster frondosus (Nutt.) T. & G. 



Annual; stems 2-5 dm. tall, leafy, glabrous or nearly so; leaves linear to 

 linear-lanceolate, 3-10 cm. long, entire, acute to obtuse, glabrous but somewhat 

 ciliate; heads numerous, paniculate on the branches; involucre 5-8 mm. high, 

 campanulate; phyllaries in 2 or 3 series, almost equal in length, oblanceolate to 

 oblong-oblanceolate, obtuse to abruptly acute and often cuspidate, with a distinct 

 midrib, glabrous to somewhat ciliate; rays lacking or minute and shorter than the 

 pappus; achenes appressed-pubescent; pappus copious, white. 



In wet to moist or dry usually saline soils, in Ariz. (Apache, Navajo and 

 Coconino cos.), Aug.-Sept.; Wyo. to Ore., s. to Ariz, and Calif. 



6. Aster falcatus Lindl. 



Perennial plants from rather long rootsitocks; stems about 20-40 cm. tall, 

 branching from the base or above, the branches not especially recurved, glabrate 

 or sparingly strigose; leaves 2-5 cm. long, linear, entire, ending in a callus point, 

 crowded, glabrate to sparingly strigose; heads 1 to few on the branches, not 

 secund; involucres 4-6 mm. high, hemispheric to turbinate; phyllaries oblanceo- 

 late, acute to a callus point but tips little if any reflexed, rather thin, glabrate 

 to sparingly strigose; rays 3-5 mm. long, white to pinkish; achenes appressed- 

 hairy; pappus bristles many, whitish or tawny. 



In water of cataracts below springs and in seepage area, in N.M. (rather wide- 

 spread in mts.) and Ariz. (Coconino Co.), Aug.-Sept.; Mack. s. to Kan., N.M., 

 Ariz, and Calif. 



1621 



