14 



MORPHOLOGY 



appears in the young plant let, until that has established itself 

 and hail time to elaborate proper material therefor. This con- 



dition U correlated with thin foliaeeous 

 cotyledons, holding no store of noiiri-h- 

 ineiil. Here they do not contain sullicieiit 

 material for the development of the initial 

 stem and root. The maternal provision 

 for this is here stored up in the seed 

 around hut not within the embryo. This 

 nourishing deposit, seen in the section 

 (Fit;-. \:\) filling the whole space iietween 



the seed-coats and the thin embryo, was 

 named by the early botanists and vege- 

 table anatomists the Ai.r.t MKN of the seed. 1 

 This substance, softened in germination 

 and by chemical changes rendered soluble, 

 is gradually absorbed by the cotyledon^ 

 as material for their growth and that of 

 the developing primary stem and root. 



26. Seeds in this regard are accordingly 

 distinguished into albuminous and <>.nil- 

 l>itin!>i<niSi those supplied with and those 

 destitute of albumen. The dittereiice 

 inheres neither in the character nor in 

 the amount of the maternal provision for the development of 

 the euibiyo-plant. but merely in the storage. In cxalhinninous 

 seeds the nourishment supplied for this purpose is taken into 

 the embryo itself, mostly into the cotyledons, during the growth 

 and before the maturity of the seed. In albuminous seeds 

 this same material is deposited around or at least external to 

 the embryo. 



27. The amount of this deposit is, in the main, inversely pro- 



1 (irew appears to have lirst applied this name, and Gaertner to have 

 introiluccil it into systematic botany, where it remains in use, although 

 Jussieii replaced it by the term /',//>///, and Richard by /.'//</>/////, 

 neither of them much better etyinolo^ically than the old word Allmnn n. 

 But it must be kept in mind that it was intended to liken the " albumen " of 

 the seed with the albumen or white of an CLIU' as a liody or mass, and not as 



a chemical suh-taiiee; the embryo bein.u' fancifully conceived to be analo- 

 gous to the //'<// of the co-tr, the surrounding substance of this kind not 

 unnaturally took the name of the //////., viz. albumen. 



FIG. 13. Section of seed of common .Morning Clory. l]>nnca purimrea. <livi<ling 

 the contained cmln-yo tlinviiirli tin- crnt iv. 1 1. l-'.nihryo of same, il.'tarh.'il ami straiulil- 

 -iic(l. I.',. iMnLryo in ^rrinination ; tin 1 cotyledons only partly ili'taclird from tlir coat 

 <'!' tin- seed. Hi. Same, later and more developed, the cot\lrdons unfolded and <>ui- 

 spi cad as the tirsl pair of leaves. 



16 



