FLORA OP THE GALAPAGOS ISLANDS. 159 



longis. — Charles Isl. : Snodgrass & Heller, no. 452 (hb. Gr.); 

 Baur, no. 41 (hb. Gr.), and (?) Baur, no. 42 (lib. Gr.). 



Forma duncanensis, inarmata ; foliis anguste lanceolatis, base 

 apiceque acutis. — Duncan Isl. : Baur, no. 47 (hb. Gr.). Perhaps 

 only a young form. 



Forma jacobensis, spinis perbrevibus armata ; foliis late oblongis, 

 iutegerrimis, basi apiceque rotundatis mucrouatis supra lucidis et trans- 

 verse rugulosis 1-1. 3cm. longis. — James Isl. : a shrub 3 to 6 dm. high, 

 in sand near beach, James Bay, Snodgrass & Heller, no. 364 (hb. Gr.). 



Forma jervensis, spinis brevibus gracilibusque armata ; foliis late 

 oblongis iutegerrimis 1.7 cm. longis apice rotundatis margiue valde 

 revolutis supra baud lucidis. — Jekvis Isl. : Baur, no. 46 (hb. Gr.). 



These forms possess, as will be seen from the above brief characters, 

 rather strikiug differences. It is, however, very difficult to tell how 

 much of this variation is due to permanent divergence of character aud 

 how much to individual environment and age. The species as a whole is 

 very near C. JVicholsonii, Hook., but the branches do not exhibit the ten- 

 dency to induration at the tip so conspicuous in the species just mentioned. 

 C. galapageia was also collected by Habel ace. to Hemsl. in litt. 



BURSERACEAE. 



BURSERA, L. 



B. graveolens, Trian. & Planch. Ann. Sci. Nat. ser. 5, xiv. 303 

 (1872) ; Engl, in DC. Monogr. iv. 49. Elaphrium graveolens, HBK. 

 Nov. Gen. & Sp. vii. 31 (1825). E. Tacamaco, Tul. Ann. Sci. Nat. 

 ser. 3, vi. 368 (1846). Spondlas Edmonstonei, Hook. f. (3), 230; 

 Anderss. (1), 243, & (2), 106; Rob. & Greenm. (1), 145. Guaiacum, 

 Baur, Am. Nat. xxv. 220. — Galapagos Ids. : Goodridge (hb. Gr.) ; 

 Habel. Abingdon Isl. : common, large, extending from the beach to 

 350 m. alt., Snodgrass & Heller, no. 809a (hb. Gr.). Albemarle 

 Isl.: Macrae; southern part, Baur, uo. 58 (hb. Gr.) ; Elizabeth Bay, 

 abundant on the north shore, Snodgrass & Heller, no. 259 (hb. Gr.) ; 

 Iguana Cove, Snodgrass & Heller, no. 21 (hb. Gr.) ; mountain east of 

 Tagus Cove, Snodgrass & Heller, no. 227 (hb. Gr.). Barrington 

 Isl. : small and leafless, 28 May, ace. to Mr. Heller. Charles Isl. : 

 Edmonston, ace. to Hook, f., 1. c. Chatham Tsl. : rather common, ace. 

 to Mr. Heller. Hood Isl. : scattered and rather small, ace. to Mr. 

 Heller. Indefatigable Isl. : Steindachner in hb. Vienna Mus., ace. 

 to Engl. 1. c. ; common on the north coast, ace. to Mr. Heller. James 



