SEEDS 209 



pine, the embryo is polycotyledenous, having five cotyledons; 

 in the monocotyledons, represented by the lily, there is only 

 one cotyledon ; while in all dicotyledenous plants, represented 

 by lobelia, there are two cotyledons. 



The hypocotyl is the embryo-stem which bears the plumule 

 and cotyledon or cotyledons. 



The caulicle is the end of the hypocotyl and it develops 

 the primary root. 



In studying and identifying seeds it is necessary to note 

 their outline, size, color, surface, texture, odor and taste. 



Outline. The outline of seeds is made up of curved sur- 

 faces, plane surfaces or of curved and plane surfaces. Refer 

 to the chart on leaf outlines for typical forms. 



Size. There is the greatest possible variation in the size 

 of seed but the maximum size of the seed of each species is 

 fairly uniform. The cocoanut is one ot the largest known 

 seeds and the seeds of orchids, which are microscopic, are 

 among the smallest. Between these two extremes there is a 

 series of intermediate sizes, well represented by our common 

 vegetable seeds. 



Color. The color of a seed should always be noted. Gray, 

 yellow, brown, red and black are the common colors. 



Surface. There is a great variation in the surface of seeds. 

 The surface is smooth, reticulate, furrowed, grooved, or 

 hairy. The hairs of cottonseed constitute the cotton of 

 commerce. 



Odor. Most seeds are odorless but many are fragrant 

 because of the presence of aromatic volatile constituents. 



Taste. The taste of many seeds is very characteristic. 

 The more common are pungent, sweet, astringent, bitter 

 and acrid. In tasting seeds cut away the testa and apply 

 the tongue. Such a procedure is not dangerous even in the 



case of such a poisonous seed as nux vomica. 

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