128 SEED. 



2d. The Husk, is the outer coat of the seed which, on boil- 

 ing, becomes separate ; as in peas, beans, Indian corn, &c. ; 

 this skin is also called the spermoderm from the Greek words, 

 spsrma, signifying seed, and derma skin. The spermoderm or 

 skin of the seed consists of three coats, analogous to the three 

 divisions of the pericarp ; the external skin, called the testa or 

 cuticle corresponds to the epicarp or outer covering of the peri- 

 carp ; the cellular tissue called mesosperm, corresponds to the 

 mesocarp, or middle of the pericarp ; and the internal skin or 

 endosperm corresponds to the endocarp or inside skin of the 

 pericarp.* 



The husk surrounds the kernel ; it is essential, as the ker- 

 nel which was originally a fluid, could not have been formed 

 withoutits presence. 



3d. The Kernel, includes all that is contained within the 

 husk or spermoderm ; it is also called the neuckus or almond 

 of the seed. The kernel is usually composed of the albumen, 

 cotyledon and embryo. The Albumen is that part of the kernel 

 which invests the cotyledons or lobes, and is thought to afford 

 the same support to the germinating embryo, that the white of 

 an egg does to a chicken. Both in respect to hardness and 

 colour, the albumen in many seeds greatly resembles the 

 white of a boiled egg. It is not considered an essential part 

 of the seed, because it is sometimes wanting ; but when pre- 

 sent it supports and defends the embryo, while imprisoned in 

 the seed, and serves for nutriment when it begins to germinate. 

 It has no connexion with the embryo, and is always so distinct 

 as to be easily detached from it. Albumen makes up the 

 chief part of some seeds, as the grasses, corn, &c. ; in the nut- 

 meg, which has Very small cotyledons, it is remarkable for 

 its variegated appearance and aromatic quality. It chiefly 

 abounds in plants which are furnished with but one cotyledon. 

 Fig. 85. 



Fig. 8 represents the same seed (the 

 garden bean) as seen at fig. 84 ; it hero 

 shews the cotyledons as divested of the 

 husk ; a represents the cotyledons ; b 

 and c, the embryo ; d shews the petioles 

 or stems of the cotyledons. 



Cotyledons (from a Greek word, kotule, 

 a cavity), are the thick fleshy lobes of 

 seeds, which contain the embryo. In 

 beans they grow out of the ground in 



* These three divisions may not always seem distinct, as in some cases, the 

 mesogperm is scarcely to be separated from the cuticle. 



Husk Spcrmoderm, divisions Cuticle Mesosperm Endosperm Husk 

 essential Kernel, of what composed ? Albumen Cotyledons. 



