170 TRACTS ON VARIOUS SUBJECTS, «S:c. 



and thereby protected from any depredation by goats, and where 

 nearly an adequate culture of Nopal plants may be made, at little 

 or no expense to government, without much encroaching on the 

 ground that may be thought necessary for the culture of vegetables 

 for the family inhabiting the house there ; and if even a small 

 sum was charged on the supplies of Nopal leaves furnished, to 

 reimburse any expense incurred, and for transport, if necessary, 

 to the shipping ; I should consider it proper, as attaching some 

 value to the supply, which being furnished g-ratis, might tend to 

 diminish ; — such being the general tendency of mankind to prize 

 according to the difficulty of obtainment, 1 feel the less hesitation 

 in recommending this principal culture in that garden, as its 

 object as a Botanical Garden has been frustrated, and from its 

 limited scale, and the little that is growing in it of a foreign and 

 valuable nature : from the many seeds from many quarters, and 

 particularly from India, that have been forwarded, it would seeui 

 badly calculated for the continuance of such an object. But for 

 the culture of the Kew Nopal, it will answer well, the only 

 thriving plants of this Cactus being there ; the very few at Plan- 

 tation-house and Long Wood being of so stunted a growth, 

 though long in the ground, as to show that either the ground 

 or the elevation is not favourable to the luxuriant growth of this 

 esculent plant. There is also another species of Cactus growing 

 in the Botanical Garden of a large size, what Dr. Anderson 

 called the China Nopal : I wish attention to be paid to this dis- 

 tinction in making plantations, as the Kew Nopal is alone the 

 object of culture as a viegetable ; the leaves of the Kew Nopal are 

 more retuse, narrower, and less thick, >vith fewer and shorter 

 thorns, and the full grown leaves, not too old, are of a dark green, 

 while the other, or China Nopal leaves are of a lighter green, and 

 with a less lucid surface : these distinctions will prevent any 



