34 THE CACTACEAE. 



cultivated and may be found throughout the warmer parts of the world. Two are of 

 some economic importance and two or three are grown as ornamentals. 



The name Nopalea is doubtless from nopal, the common name of Mexicans for certain 

 opuntias and nopaleas. 



Key to Species. 



Spineless, or rarely a few short spines on old joints ■ i. N. cochenillifera 



Joints spiny (spines few in N. auberi). 



Spines, at least those of young joints, very slender, acicular, several at each areole. 



Spines white 2. N. gualemalensis 



Spines yellow or becoming brown. 



Joints obovate to oblong, 10 to 22 cm. long, 5 to 10 cm. wide 3. N. lulca 



Joints linear-oblong to oblong-lanceolate, 6 to 12 cm. long, 2 to 3 cm. wide 30. N. gaumeri 



Spines stouter, subulate. 



Areoles with i or 2 spines, or spineless; joints glaucous 4. N. auberi 



Areoles with 2 to 4 spines; joints green. 



Joints linear or linear-oblong, 4 to 7 times as long as wide 5. N. dejecta 



Joints oblong or oblong-obovate, 2 to 4 times as long as wide. 



Spines 2 to 4; joints not tuberculate 6. N. karwinskiana 



Spines 4 to 12; joints strongly tuberculate ' 7. N. inaperta 



1. Nopalea cochenillifera (Linnaeus) Salm-Dyck, Cact. Hort. Dyck. 1849. 64. 1850. 



Cactus cochenillifer Linnaeus, Sp. PI. 468. 1753. 



Opun'ia cochinelijem Miller, Gard. Diet. ed. 8. No. 6. 1768. 

 Often tall plants, 3 to 4 meters high, with trunks up to 2 dm. thick; branches of ascending or 

 spreading oblong joints, sometimes 5 dm. long, green, bright green at first; spines none or rarely 

 minute ones develop on the older joints; glochids numerous, caducous; leaves small, awl-shaped, 

 soon deciduous; flowers appearing from the tops of the joints, usually in great abundance; flower, 

 from base of ovary to tip of style, 5.5 cm. long; ovary nearly globular, 2 cm. long, with low diamond- 

 shaped tubercles, its areoles iDearing many glochids; sepals broadly ovate, acute, scarlet; petals a 

 little longer than the sepals, otherwise similar, persistent; stamens pinkish, exserted i to 1.5 cm. 

 beyond the petals; stigma-lobes 6 or 7, greenish, exserted beyond the stamens; style swollen just 

 above its base into a broad disk; fruit red, about 5 cm. long, rarely maturing in greenhouse plants; 

 seeds about 5 mm. long and 3 mm. wide. 



Type locality: Jamaica and tropical America. 



Distribution: Cultivated in the West Indies and tropical America; its original habitat 

 unknown. 



Opuntia magnifolia Noronha (Verhandl, Batav. Genootsch. 5*: 22. 1790), published 

 without description, is referred to this species by Schumann and others. The name 

 Opuntia mexicana, although it has been used for more than one species, first appeared in 

 Pfeiffer's Enumeratio (p. 150. 1837) as a synonym of 0. cochenillifera. Cactus subinermis 

 Link (Steudel, Nom. ed. 2. i : 246. 1840) is given as a synonym of Opuntia cochenillifera. 



The specific name of this plant was given because it is one of the species of cactus from 

 which cochineal was obtained. Cochineal was long supposed to be a vegetable product; 

 it was not until 1 703 that, by the aid of the microscope, it was definitely determined to be 

 of insect origin. The cochineal industry is of prehistoric origin. The Spaniards found it well 

 established when they conquered Mexico in 15 18, and began at once to export the product. 

 As early as 1523 Cortez was ordered to obtain and send to Spain as much as he possibly 

 could, while during the early colonial days it was one of the chief articles of tribute to the 

 crown. From Mexico and Peru the industry was taken to southern Spain, India, Algiers, 

 South Africa, New Granada (Colombia), Jamaica, and the Canary Islands. The industry 

 grew rapidly and was very profitable. The greatest source of the cochineal was probably the 

 Canary Islands. In about the year 1868 more than 6,000,000 pounds, valued at $4,000,000, 

 were exported from these islands alone, of which the largest part was sent to England. 



The cochineal insects were placed on the joints or branches of the cactus plants, where 

 they rapidly multiplied and in about four months were collected by brushing them off 

 into baskets or bags. Then, after being dried in various ways, they became the cochineal 

 of commerce. Two or three such collections were made each year. 



