PHANEROGAMIA : FLOWERS. 445 



spermodermis, tunica externa), and the internal membrane (membrana 

 interna, tunica internet, endopleura, tegmen). The first of these is 

 sometimes the outer, sometimes the inner integument, sometimes only the 

 epidermis of the one or the other ; the second is sometimes the outer 

 integument excluding the epidermis, sometimes the inner, and sometimes 

 the nuclear membrane ; and if the epidermis of the outer nuclear mem- 

 brane is developed succulent, DeCandolle has yet a third term, namely, 

 the sarcoderm ; or sometimes the outer, and sometimes the inner coat of 

 the seed may not exist. There have naturally been endless contests 

 whether the vessels run in the outer or inner seed-coats, and more of the 

 like confusions, which necessarily must arise from the unmethodical 

 manner of treating the subject. It has already been observed, that the 

 separate layers of cells of the episperm can only be referred to the 

 integuments of the seed-bud by tracing the development in the individual 

 cases ; when this has not been done, we must be content to describe such 

 layers as are distinguishable, without further talk about their unknown 

 origin. 



The albumen is either endosperm or perisperm, and its texture 

 may be fleshy, horny, or otherwise varied ; if marbled by brown, 

 half-decayed lobes of the episperm, penetrating into its substance, 

 it is said to be ruminated ; its contents are mealy, oily, &c. 



The embryo is mono-, di-, or polycotyledonous, erect, curved, 

 spiral, &c. ; enclosed in albumen, lying at the apex of this (usually 

 falsely called the base), or encircling the albumen (embryo peri- 

 phericus, albumen centrale), &c. Its position in reference to the 

 seed is invariably so determined that the point of the radicle is 

 directed to the micropyle. Through this law the whole of the 

 former temporary terminology has become quite useless, but it 

 is still retained ; it is double : 



270 



1. According to L. C. Richard, the seed, supposed erect upon its 

 base, has, A, an embryo orthotropus or erectus, if the root is directed 

 towards the base ; B, an embryo antitropus or inversus, if it is 

 towards the apex ; (7, an embryo heterotropus or vagus, when it has 

 a direction intermediate between the two; and />, an embryo am- 

 phitropus, when the embryo lies curved into a circle in the seed. 



2. The terminology of older date, still much in use, refers the 

 terms to the unchanged position of the seed in the fruit, supposed 

 to be upright, and it speaks of, A, radicula infera, when it is directed 

 to the base of the pericarp ; B, radicula super a, when it is directed 

 to the apex of the same, and, C, radicula vaga, when it is directed 



