ON CACTI AND OTHER SUCCULENTS. 



799 



resembling the shape of 

 a melon. It is unbranched, 

 and has a soft, woolly, 

 cap-like head at the 

 apex, bearing small 

 tubular rose-coloured 

 blossoms. M. com- 

 munis (Turk's Cap) 

 (Fig. 536) is most 

 remarkable ; it has 

 a globular stem, 2ft. 

 to 3ft, in diameter, 

 and on the top a 

 cap, cylindrical in 

 shape, from 5 in. to 

 i2in. in height, 

 covered with red 

 spines, which closely 

 resemble a Turkish 

 fez; the flowers, 



which are red, are ^ 



J J ' Fig. q^4. — Mammillaria elephantidens. 



produced on top. 



M. depresses, instead of having a cylindrical cap, has a broad 



tuft of red spines and 

 wool like a skull-cap. 

 M. Miquelii is oval, 

 dark green, and has a 

 cylindrical cap com- 

 posed of white threads 

 and red bristles. 



Opuntia (Indian Fig 

 or Prickly Pear). — This 

 is about the best known 

 and the most exten- 

 sively grown of all the 

 Cacti, and from one 

 species ( O. cochinelliferd) 

 the cochineal insect is 

 obtained. They bear 

 various coloured flowers 

 — yellow, red, and 

 purple — and can stand 

 a low winter tempera- 

 ture, some being almost 

 hardy. Sorts : O. arbor- 

 escens grows in the 

 form of a tree ; the 

 flowers appear on the 



Fig. 535.— Mammillaria 

 macromeris. 



