Vol. I] STEWART— BOTANY OF THE GALAPAGOS ISLANDS 109 



and uneroded as when first cooled, and it is usually in such 

 situations that it is the most abundant. The branches of this 

 species radiate upward and outward to a height of 2-3 ft., form- 

 ing candelabra-like masses. The cactus with the habit of C. 

 periivimms, mentioned by Henslow, Mag. Zool. and Bot. 476 

 (1837), probably belongs to this species. Plate V. Endemic. 



C. sclerocarpus K. Sch. in Rob. (1), 179. — Albemarle Isl. : 

 Banks Bay, an arborescent species of Cereiis was reported from 

 this place by F. X. Williams; it most likely belongs to this 

 species ; Black Bight, Snodgrass and Heller; Christopher Point, 

 Snodgrass and Heller. It was noticed, in sailing by this por- 

 tion of the island, that this species grows very abundantly on 

 the barren lava fields near the coast; Tagus Cove, occasional 

 on cinder beds in the vicinity of the cove and at various places 

 on the side of the mountain. It also occurs fairly abundantly 

 on the floor of the crater at about 3600 ft., where the conditions 

 are desert in the extreme; Villamil, in barren rocky places in 

 the vicinity of the shore, and in similar situations around the 

 base of the mountain to 100 ft. A few specimens were noticed 

 on the inside of the crater at 2750 ft., along with other xero- 

 phytic plants, (no. 2095). Indefatigable Isl.: Academy 

 Bay, abundant in dry rocky places near the coast, seldom 

 occurring any distance inland, (no. 2096). James Isl.: 

 James Bay, abundant on recent lava flows to 900 ft. south of 

 the bay. It occurs most abundantly along the edges of the 

 flows, but stops abruptly as soon as other large vegetation 

 begins to appear, (no. 2097). Narborough Isl.: south side, 

 a species of Cereus was reported by /. vS. Hunter from this side 

 of the island. It was probably this species. 



This species can be distinguished from C. galapagensis by 

 the following characters : branches few and usually parallel ; 

 articulations usually elongated, somewhat slender, 15-angled. 

 All of the flowers secured were smaller than those described by 

 Schumann, op. c. 180. The great variability in the flowers of 

 this species is well illustrated by two flowers taken from the 

 same plant on Indefatigable Isl. One of these has most of the 

 petals broadly spatulate, truncate, and slightly emarginate, 

 while the other has them mostly narrowly oblong and rounded. 



All of the species of Cereus which grow on these islands are 

 found only in the most open and desert situations. One may 



