Laphamia. COMPOSITiE. 319 



134. LAPHAMIA, Gray. (Br. Increase Allen Lapham, of Wisconsin, 

 died in 1875.) — Low suffruticulose perennials, Texano-Arizonian, growing in 

 crevices of rocks, mostly with petioled and dentate or laciniate small leaves, the 

 upper alternate, rarely all opposite ; small heads of yellow (rarely white ?) flow- 

 ers, either cymosely disposed or singly terminating the branches : fl. spring and 

 summer. — V\. Wright, i. 99, t. 9 ; Benth. & Hook. Gen. ii. 398, excl. spec. 



L. peninsulAris, Greene, Bull. Calif. Acad. i. 8, is an extra-limital species (with rather 

 large and radiate heads and no pappus) from Lower California. 



§ 1. Pappothrix, Gray, 1. c. Pappus of about 20 unequal rigid hispidulous 

 bristles, hardly as long as the somewhat quadrangular-compressed akene, shorter 

 than the corolla : rays none : disk-flowers 12 to 15 ; the corolla with short proper 

 tube and cylindraceous throat : bracts of the involucre 5 to 8, linear-obloncr, nearly 

 plane : stems slender, a span or more high and much branched from the stout 

 woody base : leaves mostly opi)osite, as broad as long, abruptly slender-petioled : 

 short-peduncled heads rather scattered. 



L. rupestris, Gray, 1. c. Pubescent, slightly viscid, leafy to summit : leaves (lialf-inch 

 long) sometimes crenately sometimes strongly and acutely dentate or almost laciniate : 

 pappus much exceeding short proper tube of the corolla. — IS. W. Texas, Wright, Bigelow. 



L. cinerea, Gray. Tomentose-canescent : leaves more orbicular, almost entire : pappus 

 hardly surpassing the proper tube of tlie corolla, which is more than half the length of the 

 short-cylindraceous throat: akenes sometimes 4-nerved. — Bot. Mex. Bound. 82. — IJocks 

 along Escondido Creek, S. W. Texas, Bi(/elow. 



§ 2. LaphXjiia proper. Gray, 1. c. Pappus of a solitary very slender bristle 

 (very rarely a pair from the same angle), or none : akenes flatter : disk-flowers 

 15 to 20; their corollas with longer and glandular tube. — Monothrix, Torr. in 

 Stansb. Exped. 389, t. 7, 



* Involucre 15-20-flowered, of nearly as many plane and linear pubescent bracts : leaves nearly 

 orbicular in outline, palniately lobed or dissected, not punctate, the lower opposite. 



L. Lemmoni, Gray. Depressed and diffuse, much branched, hardlj' a span high, villosely 

 puliescent, leafy throughout : leaves a quarter or third of an inch in diameter and with 

 petiole of equal length, obtusely 3-lobed and the lobes coarsely crenate-deutate : heads (3 or 

 4 lines long) short-peduncled : r.ays none: akenes canescently puberulent : pappus a very 

 delicate bristle, or occasionally a pair from the same angle, little surpassing the proper tube 

 of the corolla, or often none. — Proc. Am. Acad. xvi. 191. — Southern Arizona, near Camp 

 Lowell, Lemmon. 



Var. pedata, Gray, 1. c. Leaves pedately parted and cut into narrow lobes. — With 

 the other form, also on the Chiricahua Mountains, Lemmon. 



* * Involucre 15-25-flowered, rather narrow, glabrous, of thinnish nearl}' plane bracts, 2 or 3 

 lines long: herbage merely pubendent: leaves mostly angulate-toothed or incised, tlie lower 

 opposite : heads commonly corynibosely cymose and pedunculate. 



L. halimifolia, Gray. Stems a span or more high and crowded on a thick woody caudex : 

 leaves coriaceous, resinous-punctate or atomiferous, somewhat viscid, broadly ovate or rhom- 

 bic, seldom inch long, laciniately dentate, al)ruptly long-petioled : rays 4 to 6, with broad and 

 short ligules little longer than the tube: pappus none. — PI. Wright. I.e. 99, t. 9. — S. W. 

 Texas, Wn'(/ltt, Bi(/eloiv. 



L. angustifolia, Gray. Leaves lanceolate or rhombic-lanceolate, tapering into margined 

 petioles, laciniately 1-5-toothed or lobed : heads less numerous, scattered : rays none : other- 

 wise much like the preceding species. — PI. Wright. 1. c. & ii. 81. — S. W. Texas, on high 

 and rocky hills of the Pecos, Wright, Ilavard, the latter's specimens connecting with var. 

 laciniata, Gray, Bot. Mex. Bound. 82, which proves to be only a form with long and weak 

 stems, hanging from rocks on the Rio Grande, Bigelow, Schott. 



