July 1891.] BOTANICAL SOCIETY OF EDINBURGH. 185 



Maximiliana Martiana ; (7) Guliclma spcciosa ; (8) Latania 

 loi'lonica ; (9) Coco-nut palm ; (10) African Oil palm ; 

 (11) Papaw tree (Carica Papaya) ; (12) Silk-cotton tree 

 {Eriodendron) ; (13) Bread-fruit tree {Artocarpus) ; (14) 

 Brocchinia cordylinoidcs ; (15) Victoria regia. 



Note. — In the preparation of this paper I have heen 

 indebted to two works by Mr E, F. im Thurn, — his pamphlet, 

 " On the Palms of British Guiana," and his book, " Among 

 the Indians of Guiana." The measurements of palms are all 

 taken from the former. 



The Leaves and Stipules of Larrea mexicana, Moric. 

 By John H. Wilson. D.Sc, F.R.S.E. 



(Read at the Meeting of the Society on March 12, 1891.) 



The genus Larrea is confined to desert regions of America. 

 Argentina is the home of three species : — L. nitida, L. 

 divaricata, and L. cuneifolia. L. mexicana extends over a wide 

 area, comprising Southern California, Nevada, Utah, Arizona, 

 New Mexico, Western Texas, and Mexico. It is particularly 

 abundant in the Mohave (Mojave) desert, where the material 

 I have studied was gathered by Mr A. H. Gibson. As it is 

 evergreen and thrives in arid regions, it is the means of 

 making leCtge tracts verdant which without it would be 

 desolate. The rainfall it requires is stated to be 3 

 inches per annum. It bears yellow flowers in early summer. 

 Its native names are " Palo ondo," " Tasajo," " Gabernadora," 

 " Hideondo," " Etiontio," and " Guamis." Its English title is 

 Creosote-bush or Creosote-plant. In Northern Mexico its 

 height is 8 feet, in Texas and New Mexico it is only 

 3 or 4 feet. 



There is no mistaking the plant in its native habitat. 

 The foliage is bathed in a very viscid substance having a 

 peculiar, strong, aromatic odour, somewhat resembling that 

 of creosote. The surrounding atmosphere is tainted by it, 

 and animals habitually shun the bush. Its presence is a 

 sure indication of a " sterile worthless soil." ^ Durand and 



* Bigelow, Report of the Botany of Lieut. Whipple's Surveying Expedition 

 in 1853-54, Washington, 1856. 



TRANS. BOT. SOC. VOL. XIX. O 



