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84 FLOWERS. 



The pappus, or seed down is generally attached to seeds wanting 

 a pericarp, as with the compound flowers, dandelions, thistles, &c. 

 In the first the pappus is elevated on a stype above the seed ; and in 

 the second it is sessile or sitting on the seed. 



Flowers. 



These are an important organ of plants. They are designed for 

 the protection of fruit and the reproduction of their species by the 

 agency of seeds, and are the means, also, by which these species are 

 determined by botanists. 



They consist of several parts or organs, differing much from one 

 another, but collectively, of the floral envelops and the sexes. The 

 first consists of the calyx or flower-cup, the outer green envelop and the 

 corolla, blossom, or inner envelop, the colored part of the flower. Each 

 part of the envelop consists of parts or leaves, which, in the calyx, 

 are called sepals and in the corolla petals. 



One or both of these envelops is often wanting in plants ; in the 

 calyx, as with the tulip and lily ; and in the corolla, as with most forest 

 trees. The sexes consist of the stamens, pistils, &c. The pericarp 

 and seed are also distinct parts of flowers. 



The calyx is an expansion of the outer bark of the flower-stalk. 

 It envelops the corolla before it expands, and subsequently remains, 

 or falls off, as with the poppy. It consists either of one leaf, or sepal, 

 and is called monosepalous, or of several sepals, and is 

 polysepalous. This cut shows a monopetalous calyx, or 

 flower-cup, five-parted., as in burglass, tobacco, etc. When 

 surrounded by another it is double, and when belonging to 

 many flowers it is common. It is composed of 3 parts ; the tube, 

 rising from the base ; the throat, the part above the tube, and the 

 mouth, the upper expanded part. It is a curtain in mushrooms, etc., 

 and a veil in grasses, grains, etc. The scales are husks of one piece 

 in rye and many pieces, as in panic-grass. 



The position of the calyx in relation to the germ is important in 

 marking the distinctions of genera, or natural families. It is superior 

 when at the top of the germ, as in the apple, etc., and inferior when 

 below it, as in the pink. It is called caducous when it falls off before 

 the flower expands, and when it falls off with the corolla it is decidu- 

 ou,s, and when remaining till the fruit is mature it is persistent, as with 

 the apple, pear, pea, etc. 



The divisions of the calyx are 1st, the perianth, the real calyx, or 

 cup, as in the rose : this is double in some, as the hollyhock ; 2d, 

 involucrum, as in the carrot, etc., in which the calyx does not 



