1922] Joh^istmi: Vndescrihed Plants Mostly from Baja California 443 



Mentzelia hirsutissima var. nesiotes var. nov. 



Corolla aurantiaea ; f oliis 1-2 em. latis, crasso-dentatis. 



Type.— San Benito Island, March 28, 1897, T. S. Brandegee. Sheet 

 no. 138558 in Herb. Univ. Calif. 



Typical 31. hirsutissima Wats, is known only from the type locality 

 on Angel de la Guardia Island, where in 1921 I re-collected it in a 

 small-flowered form. The species differs from M. involucrata in its 

 more narrow green, instead of broad scarious, bracts. There are two 

 varieties of M. hirsutissima, one from the peninsula of Baja California, 

 and the other, the one here described, from the west-coast islands. The 

 first variety may be called M. hirsutissima stenophylla n. comb. (M. 

 stenopliylla Urb. & Gilg, Nov. Act. D. Akad., 76:80. 1900). In the 

 species and in the variety nesiotes, the middle lobe of the anthers 

 equals or exceeds the lateral lobes, but in the variety stenophylla the 

 middle lobe is greatly elongated and twice the length of the lateral 

 lobes. The variety stenophylla ranges over the northern third of Baja 

 California. The variety nesiotes is kno"\^Ti only from San Benito, 

 Natividad, and Cedros islands, from which it has been reported as 

 M. involucrata (Zoe, 5:22-24. 1900) ; it is characterized by its orange 

 corolla, and not very thick coarsely toothed leaves. Possibly the 

 variety nesiotes is the basis of the report of M. triciispis from Cedros 

 Island (Urb. & Gilg, op. cit., 80), but Palmer 712, cited as the basis of 

 that report, is determined as M. adherens by Vasey and Rose (Contr. 

 U. S. Nat. Herb., 1:16. 1890). 



Mentzelia involucrata var. megalantha var. nov. 



Fetalis 3.5-4.5 cm. longis. 



Type. — Near Salton. Riverside County, California, April 21, 1905, 

 Hall 5839. Sheet no. 68744 in Herb. Univ. Calif. 



The species is characterized by its large, white, scarious, green- 

 marginecl floral bracts. In California it is most common in the 

 Colorado Desert from which it extends eastward into Arizona. The 

 species occurs in two forms, which are sharply separated by their 

 flower size. The typical form of the species is the small flowered plant, 

 with petals 1.5-2.5 cm. long, for in the original description Watson 

 gives the length of the petals as " an inch. ' ' The flowers in the variety 

 megalantha are very large and much resemble those of M. laevicaulis. 

 The variety ocurs only in the Colorado Desert, where, judging from 

 the relative amounts of material, it is less common than the species. 



