Rafinesquia. COMPOSITE. 429 



S. MYRIOCLADA, Eaton, 1. c. t. 20, of Northwestern Utah, is a more slender perennial species, 

 with smaller 3-flowered heads ; and 



5. THURBERI, Gray, PI. Thurb., a larger-flowered annual or biennial of Arizona and New 

 Mexico. These are the only recognized species, besides those here described. 



* * Involucre broader, about \Q-flowered, and with some outer scales of intermediate 

 length : stems leafy to the top ; the short peduncles mostly naked. 



6. S. lactucina, Gray. Stems a span or two high from a perennial root, 

 corymbosely branched : leaves linear or lanceolate, runcinate-denticulate or entire, 

 elongated : involucre half an inch long, of 6 to 9 inner scales, a few looser calycu- 

 late ones, and one or two of intermediate length and character : akenes oblong- 

 linear, terete, very smooth, the ribs slender. Proc. Am. Acad. vi. 552. 



Wooded region of the Sierra Nevada, at about 5, 000 and 6, 000 feet, in and near the Mariposa 

 Sequoia grove (Brewer, Bolander} ; also in the northern part of the State, at McCumber's (New- 

 berry), and pine woods of Mount Shasta, Brewer. Leaves 2 to 4 inches long, 2 to 4 lines wide. 

 Flowers delicate rose-color. 



3. Heads larger \ about \1-flowered: scales of the campanulate involucre more 

 numerous and imbricated in about 3 series, the outer successively shorter : 

 receptacle alveolate, and the margins of the alveoli Jimbriolate-hirsute : bristles of 

 the pappus 15 to 20, short-plumose for their whole length. ALLOSERIS, Gray. 



7. S. cichoriacea, Gray. Minutely tomentose-puberulent when young, rigid : 

 stem 2 feet or more high, leafy below, and with virgate branches naked above : 

 leaves coriaceous, lanceolate, runcinately toothed, the teeth rigid : heads somewhat 

 racemose or panicled, short-peduncled : scales of the involucre rather loose and 

 rigid, lanceolate : young akenes short and smooth : pappus sordid or dull white. 

 Proc. Am. Acad. vi. 552. 



Near Fort Tejon, Dr. Horn. Leaves 4 or 5 inches long (the lower unknown), not unlike those 

 of Cichory, but rigid. Involucre fully half an inch high. Corollas probably rose-color. An 

 ambiguous plant, both on account of the involucre, to which, however, the preceding species 

 leads up, and especially on account of the alveolate receptacle, the short-plumose pappus, and its 

 dull hue. 



CH^TADELPHA WHEELERI, Gray, Proc. Am. Acad. ix. 218, discovered in Southern Nevada 

 on the borders of Arizona, has been recently detected in N. W. Nevada, by Lemmon and Case, so 

 near the border of the State that it may be expected within. The plant has the aspect of a Ste- 

 phanomeria, or of a Lygodesmia ; but the akenes of the five flowers are severally partly enclosed 

 in the carinate base of the subtending scales of the involucre, and the pappus consists of five 

 rigid awnlike naked scales, having a few shorter bristles adnate to their base, 3 to 5 on each side. 

 The root is perennial. 



111. RAFINESQUIA, Nutt. 



Head many- (1530-) flowered. Involucre conical-cylindraceous, of 7 to 15 

 equal linear acuminate principal scales, and a few loose and shorter calyculate ones. 

 Receptacle naked, flat. Akenes terete, slender, obscurely 5-ribbed or angled (nearly 

 smooth and glabrous, or the outermost pubescent), gradually attenuated into a slen- 

 der beak; the broad base hollowed at the insertion, but destitute of a distinct callos- 

 ity. Pappus white or whitish, of 10 to 15 capillary bristles which are softly long- 

 plumose from the base to below the tip. Leafy-stemmed and branching glabrous 

 annuals ; with pinnatifid leaves partly clasping at base, and rather large heads 

 terminating the paniculate branches ; corollas white or flesh-color. Nutt. in Trans. 

 Am. Phil. Soc. n. ser. vii. 429; Gray, PL Wright, ii. 103. 



A well-marked genus (although joined to Stephanomeria by Bentham), of two known species, 

 both Californian, and one exclusively so. The akenes are excavated at the broad insertion in the 

 manner of Scorzonera and Microseris, but wholly want the callous appendage. In the first species 

 the flowers are only transiently expanded according to Nuttall, and the appearance of all the 

 specimens conforms to this. But Dr. Bolander has found them open during the whole day. 



