MISCELLANEOUS PAPERS. 205 



contents of the embryo sac. A rapid development and synthesis of 

 ])art8 follow, and as a result, we have the embryo, the germ of life, from 

 which the future plant is developed. 



We now have but one step to take to bring- us to the perfected 

 seed, viz, : the deposit of the food or albuminous p3,rt of the seed. 

 This may be deposited in one of two ways : either within the embryo 

 sac, as in the endosperm, or around it, as in the perisperm. 



We have now traced the seed through the various stages of its 

 development, from its inception to its perfected form, and in the end 

 we find it but a matured and fertilized ovule. 



Like the ovule, it is composed of an embryo and integuments. 

 These integuments or coats vary in number from two to none. When 

 two coats are present, the inner coat, which is delicate in texture and 

 closely envelops the kernel, is called the tegmen, while the outer coat^ 

 which is more firm and thicker, is called the testa. This testa presents 

 an almost unlimited variety in form and texture. It may be hard and 

 crustaceous ; it may be baccate or drupaceous ; or, it may be covered 

 with various appendages assisting in dissemination. 



But it is in the kernel that our chief interest centers. Tbis we 

 find to be composed of albumen and the embryo. This term albumen, 

 by the way, is something of a misnomer. It is not the chemical sub- 

 stance albumen, but a cellular substance generally abounding in starch, 

 that forms the nutrient part of the seed. In texture it may be farina- 

 ceous, oily, fleshy, mucilaginous, or even bony. But whatever its 

 structure, its purpose is the same. 



In the embryo we find the foreshadowing of the future plant — a 

 minature individual, yet perfect in every part in which can be dis- 

 tinguished the beginning of root, stem and leaf. 



Here we have at length reached the completion of the crowning 

 function of vegetable life — that end toward which its processes have 

 been tending, the seed, within whose heart lies hidden the possibilities 

 of future generations. 



If the wise provisions of nature stopped here, the possibilities of 

 the continuance, to say nothing of the extension of species, would be 

 very limited indeed. But it does not stop here. The same overruling 

 intelligence that directed the secret processes in the formation of the 

 embryo does not forsake it here, but has made further provisions in 

 the structure of the seed or the nature of the surroundings, by which 

 the now fully prepared embryo may be brought into condition for 

 complete development. 



Were it not for special means for dissemination, plants would be 

 restricted to comparatively limited localities. 



