24 Contributions from the Gray Herbarium 
Kennedy, 1977. Caurrornta: Bishop, Heller, 8248; Parry & 
Lemmon, 349; Southern Belle Mine, Heller, 8336; Mojave Desert, 
Abrams & McGregor, 417. 
3c. M. caLirornica Gray, var. cedrosensis (Standley), comb. 
nov. Hesperonia cedrosensis Standley, Contrib. U. S. Nat. Herb. 
xii. 362 (1909). M. cedrosensis (Standley) Jepson, Fl. Calif. iv. 
459 (1914). — Lower Catirornia: San Quentin, Palmer, 640; 
Cerros Island, Dr. Street; Cedros Island, Palmer, 737. 
4. M. Heimerlii (Standley), comb. nov. Hesperonia Heimerln 
Standley, Contrib. U.S. Nat. Herb. xiii. 412 (1911). — LowER 
CALIFORNIA: Guadalupe Island, Palmer, 886. 
5. M. tarvis (Benth.) Curran, Proc. Calif. Acad. ser. 2. i. 235 
(1888). Hesperonia laevis (Benth.) Standley, Contrib. U. 8. Nat. 
Herb. xii. 363 (1909). — Lower Catrrornta: Magdalena Island, 
Brandegee. 
Ill. A REVISION OF MENTZELIA, SECTION 
TRACHYPHYTUM 
My attention has been called to this group because of some ex 
cellent specimens collected by Mr. I. M. Johnston in southern 
California where this section (Trachyphytum), by a few botanists 
recognized as a genus under the name Acrolasia, of the genus 
Mentzelia culminates in a number of closely allied and somewhat 
variable forms. The group has been subjected to revision by 
Urban & Gilg in their, on the whole helpful, Monographia Loasa- 
cearum but unfortunately these authors failed in this instance to 
discriminate certain plants (notably M. dispersa and M. albucau- 
lis) which are evidently distinct species. Dr. Davidson in the Bull. 
So. Calif. Acad. Sci. v. 13-18 (1906) has called attention to Urban 
& Gilg’s misinterpretation of M. albicaulis but he in turn 
failed in the correct application of certain names. His revision, 
furthermore, loses much from the standpoint of usefulness baa” 
of drawing specific lines too finely and more especially ieee 
the failure to include M. Veatchiana and other species, alth » ig 
the title of the paper ‘‘ A Revision of the Western Mentzelias 
promising and would seem to call for something more than an bl , 
count of the species supposed to grow in southern California. oh 
Rydberg (of course under the generic name Acrolasia) atten 
to distinguish, in his Flora of the Rocky Mts. and Adj- pee 
573 (1917), nine species for the area covered by his flora. He 


