INTEODUCTION. 



GEOTESQD'ENESS of form or habit is rarely found in combination 

 with floral beauty in the Tegetable world, yet no family afEords 

 more remarkable examples of this union of widely divergent qualities 

 than the great and peculiar Cactus order. In many large groups of plants 

 we find numbers possessing handsome foliage, but having only insignifi- 

 cant flowers, and in many others also when the flowers are more than 

 usually attractive the foliage appears chiefly to serve the purpose of a 

 foil to their rich or bright colours, having in itself nothing of a specially 

 striking nature. There seems to be something of Nature's economy in 

 thus developing one particular quality at the expense of others — a 

 concentration of strength, which probably has a deeper meaning than 

 we can perceive, for it is observable in the animal kingdom as well 

 as amongst plants. The Cactus family is, however, an extraordinary 

 exception, for, whether flowering or not, the majority of the plants con. 

 stituting it are distinguished by most striking characters. They do not 

 possess beautifully coloured or elegantly formed foliage to recommend 

 Ihem ; on the contrary, true leaves are absent from nearly all, but in 

 contrast to some of the most gorgeous flowers produced by plants, we 

 see unwieldy masses of vegetable matter, spherical, cylindrical, or 

 angular, armed with stout and formidable spines, and resembling what 

 we might almost imagine to be the relics of a vegetation belonging to 

 a period long prior to the development of the plant life familiar to us 

 in the present age. Such would be the first impression ; bat when 

 the brilliantly coloured rose, crimson, purple, or yellow flowers were 

 seen the observer would be led to the conclusion that while the plant 

 was advancing to so high a degree of floral beauty, one portion of its 

 constitution must have been strangely stunted and altered by some 

 external long-continued forces. There is an inconsistence of characters 

 that must impress the least observant, and this imparts an interest to the 

 plants which increases with the knowledge we gain respecting them, foi 



