OF PLANTS. 101 



reproductive apparatus, and it here distinctly shows itself 

 to be the terminal joint of the stem-organ (a vi). 



The sexual plants again separate into two divisions 

 of unequal magnitude. In the first and smaller, the 

 inflorescence is still very simple, since, on the one hand, 

 it is devoid of what is understood as a flower in common 

 life ; on the other, the seed-bud, and consequently the seed 

 developed from it, is naked and unenclosed in any germen. 

 This division, which includes the Fir tribe, the Loranthacea 

 with the parasite Misletoe, so injurious to our fruit trees 

 and a family of tropical plants the Cycadacece, is con- 

 trasted as the class of naked-seeded plants, as Gymnosperms, 

 with the covered-seeded class, the Angiosperms. In the 

 last great division of plants, it is the inflorescence which 

 especially attracts our attention. Here, too, the elements 

 of a graduated series are unmistakeable, but we must 

 first direct our observations to one more speciality which 

 separates the whole of the plants belonging to this class, as 

 it were into two parallel series of developments. As the 

 embryo is gradually developed from the reproductive cell, 

 upon the axis, which of course is first formed either one 

 first leaf is produced, wholly surrounding the axis like a 

 sheath, and completely covering its upper part ; or, simul- 

 taneously and opposite to each other upon the stem, two 

 first leaves appear, each of which half embraces it, and 

 which enclose the upper part of the embryo between 

 them. The first series are called the one-seed-lobed or 

 Monocotyledons, to which, for example, belong all 

 Liliaceous plants, Palms, Grasses, Sedges, &c. ; the second, 

 the two-seed-lobed or Dicotyledons, for examples of 

 which, common garden plants and trees may be taken. 

 The plants of the two series not only differ essentially in 

 their apparently unimportant characters, but in all the rest 



