72 REMARKABLE FLOWERS. [CHAP. 
latter are very sweet and juicy, and much esteemed 
on account of their cooling nature. One species 
(O. Tuna) attains the height of twenty feet, and as it 
produces large numbers of stiff sharp spines is exten- 
sively used as a hedge-plant. In Mexico this species 
is largely cultivated to afford food for the Cochineal 
insect (Coccus), for which purpose another species, the 
Nopal, is also cultivated. Several species of Opuntia 
have been introduced into Southern Europe, and so 
successfully that Dr. Philippi in his “ Vegetation of 
Etna,” tells us that “on the roughest lava thrives 
the Indian or Prickly Pear, of which the large, cooling 
fruits are sold at less than 2d. for thirty. This plant 
is one of the most useful presents of the New to the 
Old World, as it grows on the poorest and most 
rocky soil, where nothing else will vegetate, requir- 
ing no attention, and even its succulent-jointed stems 
are greedily devoured by goats.” 
Nature is most liberal to us in her supply of neces- 
saries and luxuries; still one could hardly expect her 
to supply us with such luxuries as toothpicks! Yet 
even these are provided ready made for us by a 
species of Echinocactus (E. visnaga). Some years 
ago a specimen at Kew was estimated to bear no 
less than fifty-one thousand of these useful articles. 
They are—as no doubt our readers have already 
guessed—the spines borne on the stems of this 
species, and really in common use among the Mexi- 
cans for the purpose mentioned, from which they 
derive the specific title of Visxaga, which means a 
toothpick. Their length is from an inch to an inch 
and a half. 
