Macbride — A Revision of Mentzelia 25 
trasts properly M. albicaulis and M. dispersa but he assigns 
specific names to plants that indubitably are mere forms of these 
species and distinguishes them by characters which obviously 
represent the variations of the individual plants. 
Mentzelia albicaulis and its immediate relatives may be dis- 
tinguished, I believe, as follows: 
a. Seeds thane vei grooved cn the angles, minutely muricate, 
mooth except under rather strong magni- 
ation. 
b. Leaves gear Sc area 0g entire or sinuate-pinna- 
tifid; petals 2-5 beehi lon 
c. Petals 2 pay 5 mm 
Middle cauline ha ves often mostly lanceolate; 
plants sates loosely branched; pods mostly over 
15 mam. long typical: osc ees 1. M. dispersa. 
Middle cauline eave es mostly ovate and plant 
densely branched; pods mostly shorter... .... lb. var. compacta, 
c. Petals about 5 mm. long bap ORM entreg meds © rela eh urea eg le. var. latifolia. 
b. Leaves lanceolate, more or less (usually deeply) pinnati- ; 
fid; corolla longer, the aptcash 6-8 mm. long.......... 2. M. affinis. 
angle), obviously minutely puberculate: 
b. Inflorescence not co ngested or at least not at all con- 
cealed in bract-like ficral leaves. 
c. Petals 2-4 mm. long; leaves entire or sinuately (in- : 
Ge ate deeply) poe typical. ..-..:.. . M. albicaulis. 
c. Pi jeg Het _long; ves various but mostly 
ifid. 
d. osesply i stint less than 1 em. wide, the petals 
mm. long; sepals about 3 mm. lon ng 
var. Veatchiana. 
d. Corolla 1 em. or more wide; song often 10 at 
long; sepals about 5 mm 
Corals golden-yellow; seeds ee arenas 
grooved on one angle............--+++- 3b. var. gracilenta. 
Corolla coppery-orange at base; seeds irregularly 
angled, usually not definitely grooved on one 
a. SO AG ae A eid pare ares ey var. pectinala. 
b. Etencication on congested and more or less concealed in the 
bract-like floral leaves. 
Bracts “rtogew ll ovate; leaves mostly sinuately 
toothed or pinnatifid; typical...........-.----- 4, M. ee 
Bracts ovate-lanceolate; leaves Rag entire. .4a. var. Davidsoniana 
- M. pispersa Wats . Aead. xi. 115, “ Ragh 
Dougl., var. iene ne Wats. Bot. t. King E 
caulis 
(sit) M. integrifolia (Wats.) Rydb. Mem. N.Y. Bot. Card. 3 i. 
271 (1900). M. albicaulis Dougl., var. genuina Urb. & Gilg, Nova 
oa tiga C.L.C.G. Nat. Cur — Aa ston M. Ps | 
ull. So. Calif. Acad. Sci. ii. 69 (1 
Heller, Muhl. ii. 99 (1905). A. integrifolia (Wats.) Raab. Bull. 
‘Torr, Club, Xxx, 278 (1903). A. dispersa (Wats.) Davidson, : 
- Calif. Acad. Sci. v. 14 GO A. desertorum Davidson, 1. ¢. 

