336 



ORGANOGRAPHY. 



relations to each other in the seed us in the ovule. Thus 

 the liilum and chalaza are contiguous to each other in an or- 

 thotropous seed, and the micropyle is removed to the opposite 

 end ; in a campylotropous seed the hilum and chalaza are also 

 near to each other, and the micropyle is brought round so as to 

 approach the hihim; in an anatropous seed the chalaza is re- 

 moved from the hilum and placed at the other end, while the 

 micropyle and hilum correspond to each other; while in amphi- 

 tropous and semi-anatropous seeds, the chalaza and micropyle 

 are both removed from the hilum, and placed transversely to it. 



Almost all seeds, like ovules, are enclosed in an ovaiy, the 

 only real exceptions to this law being the Coniferie and Cyca- 

 daceaj, already referred to under the head of the Ovule ; 

 and hence the division of Phanerogamic Plants into two 

 classes, called respectively Gymnosperms and Angiosperms; 

 the former including all plants which have naked seeds, the 

 latter those in Avhich they are more or less enclosed in an 

 ovary. The means of distinguishing small fruits from seeds 

 have been also already described. (See p. 299.) 



In describing the position of the seed in the ovary, the same 

 terms are used as already mentioned under the head of the 

 Ovule. (See p. 329.) Thus a seed may be erect, inverse or 

 pendulous, suspended, ascending, &c. The number of seeds con- 

 tained in the pericarp is also subject to variation, and corre- 

 sponding terms are used accordingly; thus we say the pericarp 

 is nionospermoiis, hispernwus, trispermous, quadrispermous, quin- 

 quespermous, multispermous, &c., or one-seeded, two-seeded, 

 three-seeded, four-seeded, five-seeded, many-seeded, &c. 



The seed also varies much in form, and, in describing these 

 variations, similar terms arc employed to those used in like 

 modifications of the other organs of the plant. Thus, a seed 



Fig. 726. Fig. 727. Fig. 728. Fig. 729. 



Pig. 72r.. Rounded seed of the Wnter-Cress iNasturiium offu-innle). Tlie 



testa in reticulated or netted /Vf/. 727. Reniform or kidney-shaped seed 



of the Poppy, witli un alveolate or pitted testa Fin. 728. Obovate seed 



of the Larkspur {Delphinium), the testa of which is marked with ridues and 



furrows Fig. 72y. Seed ot duckweed (Stetlaria), the testa of whicli is 



tuberculuted. 



may be rounded, as in the Nasturtium (fig. 726), ovate, as in 

 Poll/gala (fig. 736), oval, as in Asclepias (fig. 732), obovate, 



