206 FRUIT. 



The unripe seed is attached to its receptacle by a 

 system of vessels which convey to it nourishment suf- 

 ficient to effect the developement of its different parts. 

 When the seed reaches its maturity these vessels are 

 broken, and the place to which they were attached 

 remains conspicuous on the surface of most seeds. It 

 is denominated the Scar, (Hilum,) and near it we fre- 

 quently find a minute orifice through which the water 

 is absorbed during germination. 



The exterior coat of the seed (Testa) is usually firm ; 

 and being formed previous to the internal organs, it com- 

 municates to them its peculiar figure. In the mature 

 Apple it is brown, in the common Bean it is white, in 

 the Indian corn it is straw-coloured and glossy, in the 

 Rice it is pellucid, and in the Fumitory it is black and 

 shining. During germination this integument bursts 

 in consequence of the enlargement of its contents. It 

 is not unfrequently lined with a delicate membrane 

 which more immediately invests the enclosed organs, 

 being in some cases entirely di:4inct from the exterior 

 covering of the seed, and often inconspicuous, in con- 

 sequence of its intimate union with the adjacent parts. 

 In examining the internal structure or kernel of the 

 seed, we find, what botanists denominate, the Albumen, 

 Vitellus, Cotyledons and Embryo. 



The Albumen^ so named from its resemblance to the 

 white of a boiled egg, occurs in many seeds, and is 

 particularly abundant in the Grasses, Lilies and Palms. 

 It often encloses the Embryo, and has, by some writers, 

 been denominated the Perisperm, in allusion to its 

 peculiar situation, but in many cases this name is not 

 appropriate. During germination the albumen is dis- 

 solved, and converted into the first aliment of the 

 young plant. It is according to Gaertner, always dis- 



