398 COMPOSITE. Dysodia. 



leaves alternate, small, mostly 3 - 5-parted into linear-lanceolate or subulate divis- 

 ions, which are seldom gland-bearing ; all the upper reduced to subulate bracts ; 

 those subtending the involucre very short and simple : scales of the involucre linear, 

 abruptty acute, beset with oblong oil-glands, coalescent : rays few and inconspicu- 

 ous : "flowers yellow " : scales of the pappus deeply parted into about 9 bristles. — 

 PI. Thurb. 322. 



Southeastern borders of the State at San Felipe (TJiurber), and Fort Mohave, Dr. Cooper. 

 Also collected at Camp Grant, S. Arizona, by Dr. Palmer, with more developed leaflets. Head 

 half to three quarters of an inch long. Rays linear, not longer than the disk, hardly surpassing 

 the style. 



2. D. Cooperi, Gray. Scabrous-puberulent, " 2 feet high," stouter than the 

 preceding and with head fully an inch long : leaves (of branch) lanceolate, rigid, 

 coarsely and spinulosely few-toothed, and parted near the sessile base so as to form 

 a pair of subulate stipule-like lateral lobes : bracts of the involucre and scales linear- 

 subulate and attenuate-acuminate, gradually passing into each other, carinate with 

 strong midrib : rays somewhat exserted, " purple " : pappus as in the preceding. — 

 Proc. Am. Acad. ix. 201. 



Southeastern borders of the State, eastern side of Providence Mountains, Dr. Coo2>er. The 

 lower leaves are probably more divided. 



86. NICOLLETIA, Gray. 



Head many-flowered, with a series of pistillate rays ; all the flowers fertile. Invo- 

 lucre cylindraceous, of 8 to 12 equal oblong scales, calyculate with one or two small 

 exterior scales. Receptacle convex, naked. Rays oblong, minutely 2 - 3-toothed : 

 disk-corollas slender, 5-toothed. Style-branches of the disk-flowers slender, con- 

 tinued into filiform acute hispid appendages. Akenes linear, slender, terete, taper- 

 ing to the base, pubescent. Pappus double ; the outer a series of capillary bristles 

 like those of Porophyllum ; the inner of 5 thin chaffy scales with midrib produced 

 into a bristle or awn, nearly equalling the disk-corolla. — Low and branching 

 glabrous annuals ; with alternate leaves, pinnately divided into a few narrowly 

 linear or subulate lobes, and short-peduncled rather large heads terminating the 

 branches. Oil-glands in the foliage and involucre few and large. Pays pink or 

 purple, the disk-flowers (always 1) yellow. — Torr. Frem. Eep. 2d Exp. 315; PL 

 "Wright, i. 119, t. 8 ; Pot. Mex. Bound. 93. 



There are two species, both rare ; one ' found near the southwestern borders of Texas, the other 

 near the southeastern borders of California. The genus was dedicated to the memory of the 

 distinguished geographical explorer and astronomer, J. N. Nicollet, under whom Fremont initiated 

 his work. 



1. N. OCCidentalis, Gray, 1. c. A span or more high : leaves thickish and 

 with short lobes, the uppermost close to the head : scales of the pappus lanceolate- 

 subulate, tapering into a short slender awn. 



Sandy banks of the Mohave River, Fremont, Dr. Cooper. The latter found it at Camp Cady, 

 and has recorded that the rays are purple, the disk yellow. 



87. POROPHYLLUM, Vaillant. 

 Head several - many-flowered, with all the flowers perfect. Involucre cylindrical 

 or cylindraceous, of 5 to 10 oblong or linear equal scales in a single series. Recep- 

 tacle small, naked. Corollas with a slender or filiform tube, and a narrow 5-cleft 

 limb. Style-branches slender, tipped with a subulate-filiform hispid appendage. 

 Akenes long and slender, nearly terete, striate or angled. Pappus of copious rather 



