On the Classification of Plants. 2 1 1 



Gymnosperm means "naked-seeded." The seeds are generally hid among 

 the hard, woody leaves of a cone : the leaves do not grow together over 

 the seeds as the skin does over the seeds of an apple. If grains of wheat 

 and corn were " seeds" they would be gymnospermous ; for notliing grows 

 together over them. 



You can tell the Pine family without difficulty. But how ? " They are 

 evergreens." The larches shed all their leaves. " Their leaves are needle- 

 shaped." Those of the Salisburia on Boston Common are more than an 

 inch wide. " The wood is softer than hardwood." Basswood is softer than 

 a pine-knot. " They bear cones." The few pulpy leaves of the juniper- 

 cone take the shape of a berry. But these are exceptional freaks, and do 

 not deceive you. 



The Endogens are not so easily told from the Exogens, even though the 

 Gymnosperms stand between them. The seeds of the Exogens sprout into 

 two leaves, as the bean, pea, and maple : those of Endogens thrust out a 

 single one, or two very unequal ones. This distinction is almost without 

 exception ; but it is not easy of application. The dodders, which are Exo- 

 gens, never have leaves except in their little flowers. 



Endogens seldom have branches except to their flower-stems. Asparagus 

 is an exception. All the parts of their flowers are in threes : this is true 

 of very few Exogens. The leaves of Endogens have no branching veins as 

 those of Exogens have. Compare the leaves of grass, onions, and lilies 

 with those of buckwheat, horse-radish, or oak. But the Arum family 

 (wake-robins, Indian-turnips), though their leaves have branching veins, are 

 Endogens. 



So you see that the criteria used in classification are not perfect like 

 those for finding words in a dictionary. Bats can fly ; ostriches cannot. 

 Whales and porpoises are not fishes ; eels are not snakes ; we are not cer- 

 tain whether sponges are animals or not. But one who uses all the cfiteria 

 in his power need not go faV astray. It is most desirable that the mental 

 classification of plants should be habitual, as that of the higher animals 

 always is with all of us. 



Now let us sum up our classification of plants so far as we carry it 

 to-day : — 



