16 POPULAR FIELD BOTANY. 
hollow parts called carpels, which are either distinct from 
each other or united into one. Tach carpel consists of a 
hollow case, or ovary, extended at the pomt mto what is 
called the s¢y/e, which is tipped with the stigma, containing 
a sticky substance, to which the pollen adheres. In the 
carpels the seed is formed, and the style conveys a portion 
of the pollen to the young ovules or seeds. 
The fruit is the pistil enlarged, contaiming the seed, 
arrived at maturity. It is of various forms and substances ; 
large and fleshy, as the Apple; juicy, as the Currant; in 
pods, as the Pea; pulpy, with a stone, as the Plum; globu- 
lar and hard, as in the Poppy, &c.; or small, and looking 
like a seed, as Hemp or Wheat. 
The receptacle is the part of the flower upon which all 
the different parts are situated. The calyx is usually on 
its edge; the corolla, stamens, and pistils on the centre part. 
The greater number of plants have all these parts, but 
some have no corolla, as the genus Chenopodium, some no 
leaves, as Cuscuta, and others neither leaves nor stem, but 
the two combined, as in Lemna. 
Annual plants are those which are sown, produce seed, 
and die in the course of one year. Biennial, those which 
die the second year. Perennial, such as live for several or 
many years. 
