164 CALIFORNIA ACADEMY OF SCIENCES. 



inches long, 2-3 inches thick: exterior radial spines 0-10, 

 interior spines 10-12, 4-angled or fattened, l-lj inches long, 

 striate, stout and thick, ash -colored at base, with lighter 

 points: ovary covered with reddish spines: flowers yellow, 

 two inches in diameter: seeds two mm. wide. 



The short thick joints and branching habit combine to 

 give this species a strong resemblance to the Echinocerei. 

 The plants are about a foot high, covered with the stout 

 thorns and bear an abundance of yellow flowers. — Com- 

 mon about San Juanico and seen northward to El Campo 

 Aleman. 



Opuntia (Cylindropuntia), sp. Kesembling 0. 'prolifera. 

 Flowers purple, fruit proliferous, and maturing many seeds. 

 — Santa Margarita and Magdalena Islands. San Jorge. 



Opuntia (Cylindeopuntia), sp. Resembling 0. Bigelovii. 

 Flowers light yellow, stamens green, anthers yellow. — 

 Common at Calamujuet. 



Opuntia prolifera Engelm. The plants are sometimes 

 almost spineless. — San Ignacio and northward. 



Opuntia molesta. Stems few and sparingly branched, 4- 

 6 feet high: joints 6-8 inches long, an inch thick: tubercles 

 not prominent, few, bearing 4-6 spines less than a half-inch 

 long; and 1-3 spines 1-2 inches long: pulvillse of the ovary, 

 15-20, bearing a few short spines: fruit ovate, an inch long, 

 smooth, juicy: seeds 6 mm. in diameter, rounded, very ir- 

 regular in shape, deeply and coarsely lobed or tuberculated, 

 not evidently flattened in any direction: flowers purple, two 

 inches in diameter. — The long spines are sometimes not 

 present. — San Ignacio. 



Opuntia (Cylindropuntia), sp. — Calmalli. 



Opuntia (Cylindropuntia), sp. — Purisima, Comondu. 



Opuntia, sp. This and the following species are related 

 to 0. leptocaulis. — Agua Dulce, San Enrique. 



