100 ANALYSIS OF PLANTS. 



which flowers or leaves are secured, after being pressed in some old 

 book or soft paper to absorb the moisture- At the side of the speci- 

 men may be written the class, order, genera, species, and any remarks 

 as to locality, time, etc. If brushed over with corrosive sublimate, 

 worms will not affect them. Nothing can be more pleasing than ex- 

 cursions for the collection of specimens. A magnifying glass will add 

 much to the interest of observations. 



Classes. If the stamens and pistils are not visible, then the plant 

 belongs to the division cryptogamia. If visible it belongs to the divi- 

 sion phenogamous, including 20 of the 21 classes. If both stamens 

 and pistils are on different flowers, it then belongs to the class Dickda 

 or Monozcia, according as they proceed from the same or different roots. 

 If both are on the same flower and the anthers are united around the 

 pistil, the plant belongs to the class syngenesia ; but if the anthers 

 are separate and the filaments are united to the pistil, it belongs to the 

 class Gynandria; but if the filaments are not united to the pistil and 

 are united with each other, and are in two sets, it belongs to the class 

 Diadelphia, and if in one set, to the class Monadelphia. If the fila- 

 ments are separate, and of different lengths, (only where there are 4 

 or 6 stamens,) and the flower has, say 6 stamens, 2 short and 4 long, 

 it is of the class Tetradynamia ; if 4 stamens, 2 short and 2 long, 

 it is of the class Didynamia. If the flower has no one of the above 

 peculiarities and the stamens are more than ten, then their insertion 

 is to be considered. If inserted on the receptacle, the flower is in the 

 class Polyandria ; but if inserted on the calyx or corolla, then it is in 

 the class Icosandria. Should the flower have less than 20 stamens, 

 without any of the before mentioned distinctions, as to connection, 

 position or length, then the number of stamens, if less than 11, deter- 

 mines the class, and so with all the other 9 in the order of the class. 

 This is the analytical mode of determining the place of plants ; but 

 when they are placed together to form a species, and several of these 

 to form genera, these to form orders, and these to form classes, the 

 process is synthetical. 



For analysis simple and natural flowers should be taken, as double 

 ones often change their stamens and sometimes their petals by cultiva- 

 tion. Let, for example the pink be taken. This will be seen to have 

 10 stamens, and therefore of the class Decandria; and, as the 1st 12 

 orders depend on the number of pistils it will be seen that this having 

 2, belongs to the 2d order, Digynia. The flower must now be com- 

 pared with the different genera until its generic character be found. 

 Thus, for example, take the genus hydrangea which is calyx 5 toothed, 

 superior, etc. The calyx of the pink has 5 notches or teeth around it, 

 but is not superior. Then take Saxafraga ; calyx 5 parted, half su- 

 perior, but the pink not being half superior, take the genus Saponaria, 

 calyx inferior, leaved, tubular, 5 toothed, and calyx without scales. 



