ORDER MONOGYNIA. 235 



you to learn the classes by their appropriate names, as Monan- 

 dria, Diandria, rather than to confine yourselves merely to the 

 numbers, as 1st, 2nd, &c. Besides, the name of each class is 

 generally expressive of its character ; and will, when you un- 

 derstand its derivation, convey to you the idea of this character, 

 which, by the number alone, could not be done ; for example, 

 the term eleventh class, conveys no distinction but that of mere 

 number ; but the classical name Icosandria (from Eikosi, 20, 

 and andria, stamen), means 20 stamens ; this then reminds 

 you of the circumstance on which the class is founded. 



The name Icosandria, seems not, however, exactly well 

 chosen to represent the eleventh class, which is not confined to 

 twenty stamens, having sometimes as few as ten, and in some 

 cases nearly a hundred stamens. An American botanist* has 

 proposed to call the class Calycandria, from calyxf and an- 

 dria, as the insertion of the stamens on the calyx is the essen- 

 tial circumstance on which the class depends ; this change 

 has been approved, but the old name is still used. Thus with 

 respect to the name given to the great American Continent, all 

 allow it should have been Columbia, after Columbus, its dis- 

 coverer ; but when once custom has sanctioned a name, it be- 

 comes very difficult to overcome this authority by arguments 

 drawn from reason. We shall, therefore, in compliance with 

 the use of botanists, call the class Icosandria. 



Monogynia. 



The first genus which we meet with in this class is CACTUS ; 

 it contains many species ; a very splendid one is the Night- 

 blooming Cereus (CACTUS grandijiorus\ having flowers nearly 

 a foot in diameter, with the calyx yellow, and the petals white; 

 they begin to open soon after the setting of the sun, and close 

 before its rising, never again to blossom. Another species 

 (speciossissimus), with flowers of the colour of crimson-velvet ; 

 it is said to be still more superb than the grandiflorus ; this 

 genus belongs to a natural order, Succulenta, or juicy plants ; 

 they are in general destitute of leaves, but the stems often 

 appear like a series of thick, fleshy leaves, one growing from 

 the top of another. The different species of this genus are 

 distinguished by a diversity of common names ; when they 

 are of a round form, they are called Melon thistles ; when 

 more cylindrical and erect, Torch thistles; when creeping 

 with lateral roots, Cereuses ; and when composed of a stem 

 resembling flattened leaves, Prickly pears. 



* Darlington. t Calyx, genitive in Latin Calycis. 



Calycandria Genus Cactus Different species distinguished by a diversity 

 of common names. 



