XVl INTRODUCTION. 



and septicidal, when it opens at the ventral suture, or through the partitions. 

 When it opens transversely, the upper portion falling off entire, like a lid, the 

 dehiscence is circumscissile. 



90. A Silujue is a slender two-valved capsule, with two parietal placentae con- 

 nected by a persistent false partition. A short and broad silique is a Silicle. 

 These are peculiar to the Mustard Family. 



91. A Pqio is the fleshy indehiscent fruit of the Gourd Family, with the seeds 

 often embedded in the pulpy placentae. 



92. A Pome is the indehiscent fruit of the Apple or Quince tribe, where the 

 cells are enclosed in the enlarged and fleshy tube of the calyx. 



93. A Berry is an indehiscent fruit, with the seeds embedded in soft pulp. 



94. A Drupe consists of one or more hard or bony cells, called the Puta- 

 men, covered with a fleshy or pulpy coat, called the Sarcocarp; as the Peach, 

 Holly, &c. 



95. An Achenium is a small, dry, one-seeded, indehiscent fruit, the walls of 

 which do not adhere to the enclosed seed. When these are closely united, it 

 becomes a Caryopsls ; or when the walls are thin and bladder-like, and opcu 

 irregularly, a Utricle. 



96. A Nut is a dry, indehiscent fruit, with hard or bony walls ; as the Acorn 

 and Hickory-nut 



97. A Samara is a dry, indehiscent fruit, with its walls expanded into a wing ; 

 as that of the Maple and Elm. 



98. The collective fruit of the Pine is called a Cone or Strolnle. 



10. The Seed. 



99. The Seed is the matured ovule, and contains the Embryo, or the rudiment 

 of a future plant. The outer coat, or Integument, is called the Testa. It varies 

 greatly in texture, and is occasionally furnished with hairs, which cither cover the 

 entire seed, or form a tuft (Coma) at one or both extremities. 



100. The terms employed in describing the ovule are chiefly applicable to the 

 seed. The foramen of the ovule, which is closed in the seed, becomes the .1//- 

 cropyle, and is always opposite the radicle of the embryo. The Bear left on the 

 seed by the separation of the cord is the Hilum. It is sometimes enveloped in 

 a false covering, originating, during its growth, from the cord or from the pla- 

 centa. This is called the Aril. 



101. The Testa includes either the embryo alone, or an additional nutritive 

 substance, called the Albumen. 



102. The Embryo consists of the Radicle, the P/umufei "'"1 the Cotyledons. 

 108. The Radicle is the first joint of the stem, in germination, it elongates 



at one end to form the rout, and at the other, from B minute hud (I'lumul, ), to 

 form the stem. It is inferior when it |»oints to the base of the pericarp, and m- 

 rhefl it point- t0 its summit. 



104 The Cotyledons are the seed-leaves. Tl mbryo of the Exogenous 



Plant- hear- two of these, placed opposite (rarely three or more in a whorl), 

 while that of Endogenous Plants hears only one. Heme the former are called 

 dicotyledonous, and the latter monocotyledonous. 



105. wie ii tbi embryo is exposed to the combined influence of ah*, heat, and 

 moisture, it dev< lopi Into a growing plant This is termed Germination. 



