28 INTRODUCTION. 





5. The Drupe (Fig. 142.) is a seed, covered with a hard en- 

 docarp, a fleshy mesocarp, and a membranous epicarp. 



6. The Apple (Fig. 143.) is a fleshy fruit, containing a cap- 

 sule, or rather it is an enlarged fleshy calyx inclosing a mem- 

 branous or cartilaginous pericarp, divided into several cavities, 

 containing one or more seeds. 



7. The Berry (Fig. 144.) is a juicy fruit, which contains se- 

 veral seeds, and never bursts. The Compound Berry (Fig. 

 145.) consists of several single ones, each containing a seed. 



The Cone or Strobilus (Fig. 146, 147.) is a catkin hardened 

 and enlarged. 



VII. Of the Seed. 



The Seed is the part of the plant which is destined for its 

 propagation. It often consists of two halves, called cotyledons 

 (Fig. 148.), which at germination change into leaves. Between 

 these, on one side, is the Embryo (Fig. 148, .), consisting of 

 two bodies, one which descends into the earth, becoming a root, 

 and is called the Radicle (Fig. 143, b.}, the other, or Caulicle, 

 ascending and becoming the stem and leaves. (Fig. 148, c.) 

 The cotyledons are covered with an outer and an inner coat. 

 The depression seen externally opposite the place where the 

 embryo lies, is called the scar. The seed while growing is at- 

 tached to the parent plant by a thread called the umbilical 

 cord. 



But many seeds have only one cotyledon, which envelopes 

 the embryo ; and others have no cotyledon at all. Hence an 

 arrangement of plants into Acolyledonous, Monocotyledonotis, 

 Dicotyledonous, or having no cotyledon, one cotyledon, or two 

 cotyledons. 



Seeds are very diversified as to form, but it is only necessary 

 here to describe certain parts which are frequently attached to 

 them. 



The Pappus or Seed-down is a kind of bristly or feathery 

 crown attached to certain seeds or rather fruits. It is, analogous 

 to the calyx of other plants, 



Simple (Fig. 149.), when it consists of undivided hairs. 



Feathery (Fig. 151.), when each of the hairs is subdivided 

 like the shaft of a feather. 



Sessile, without a stalk. (Fig. 149.) 



Stipitate or Stalked. (Fig. 150.) 



Chaffy, when formed of small scales. 



