82 CALIFORNIA ACADEMY OF SCIENCES [Peoc. 4th Ser. 



shore, forest trees 20-40 ft. high above 350 ft., (no. 1744) ; 

 northwest side, common bushes above 100 ft., trees above 700 

 ft., (no. 1743) ; southeast side, common bushes, forming 

 almost impenetrable thickets, above 450 ft. It does not grow 

 as large here as it does at Academy Bay. James Isl. : James 

 Bay, common bushes on the lower parts, small forest trees 

 around 2000 ft., stunted bushes around 2850 ft. where it is 

 exposed to the wind ; northeast side, common bushes above 350 

 ft. (nos. 1745-1746). Narborough Isl.: south side, Snod- 

 grass and Heller. This species seems to be one of the favorite 

 host plants for Phoradendron Henslovii. Owing to its long 

 recurved thorns it is one of the most disagreeable bushes to 

 contend with when traveling on the lower parts of the islands. 

 Further distr. S. U. S., Mex., W. Ind., S. Am. 



SIMARUBACEAE 

 Castela Turp. 



C. galapageia Hook. f. (3), 229, (4), 262; Rob. (1), 158.— 

 Albemarle Isl.: Cowley Bay, low bushes to 1100 ft. 

 Chatham Isl. : Darwin; Baur. Hood Isl. : low bushes 

 around 600 ft. ; no specimens were taken. Endemic. 



Forma albemarlensis Rob. (1), 158. Forma jervensis Rob. 

 (1), 159. — Albemarle Isl. : Tagus Cove, common bushes on 

 the lower parts (no. 1747) ; Villamil, common bushes on lava 

 beds to 200 ft. (no. 1762). Indefatigable Isl.: northeast 

 side, common bushes 6-8 ft. high in loose ashy soil near the 

 shore. Stem unarmed ; leaves for the most part cuneate with 

 revolute margins, but some are obtusely oblong and mucronate 

 as in the specimens from Albemarle, (no. 1748) ; northeast 

 side, occasional bushes on the lower parts. The specimens 

 from this part of the island are armed, leaves usually oblong 

 obtuse mucronate, but some are lance-oblong acute, (no. 

 1749) ; southeast side, common bushes to 600 ft. Stem un- 

 armed; leaves oblong obtuse mucronate, (no. 1750). Jervis 

 Isl. : Baur. Considering the great variability of the forms as 

 shown by subsequent specimens, the form jervensis seems to 

 agree rather too closely with the type specimen of form albe- 

 marlensis to be considered as a good form. Narborough 

 Isl.: north side, bushes 5-6 ft. high on lava beds (no. 1651). 



