308 



THE SEED. 



inconspicuous, as in the ripe seed of Magnolia, -where it is at 

 length completely merged mid imbedded in the fleshy drupaceous 

 tc^ia, us shown in Fig. 670-07:.'. 



;V.H>. Crest-like or other appendages are not uncommon either 

 on the rhaphe or at the hiliiin. These are outgrowths produced 

 (luring the development of the ovule into the seed. In Sangui- 

 naria, such a crest develops from the whole length of the rhaphe 



C73 



D74 



(Fig. 673) ; in Dicentra, Corydalis (Fig. G74), &c.. from some 

 part of it, mostly from its base next the hilum. or from the 

 hilum itself, or even from just below it. Such an appendage, 

 especially when attached to the base of the seed, is named a 

 STROPHIOLE. A similar and commonly a wart-shaped appendage 

 in Euphorbia, Riciuus (Fig. G7">). &c., is prodneed by an out- 

 growth of the external orifice of the ovule, the micropyle of the 

 seed. This properly takes the name of CAIHXCLK. But the 

 two terms are not always discriminated. By further develop- 

 ment, cither of these in 33* give rise, in certain seeds, to an acces- 

 sory covering called 



597. The Aril or Arillns. This term, rather vaguely employed 

 Ity Linnaeus, was first well defined b3 r Gaertner. The true <n-!llns 

 is an accessory seed-covering, more or less incom- 

 plete, formed between the time of fertilization and 

 the ripening of the seed, by a growth from the apex 

 of the funiculus (when there is any) at or just be- 

 low the hilum, in a manner similar to that in which 

 the coat or coats of the ovule are formed. That 

 of Xympluva (Fig. G7G) is a typical example : only 

 the arillus is developed from the funiculus at a point distinctly 

 lirlow its apex : here a ring forms, which grows into a cup. and 

 this is soon extended into a sac, loosely enclosing the seed, and 

 open at the top. This is memhranaceous ; commonly it is tleshy. 

 AVlien there is absolutely no funiculus. the aril may originate 

 from the placenta, as it does in Podophyllum, in which most of 



FIG. F<~'' An.-ilropoiis seed of Sarrarenia purptirea. with very salient rhaphe. f>73. 

 Jviine of S!iiejuiii:iri:i or Hloodroot. with rhaphe crested for its whole length. I'M I Seed 

 of Corydalis aurea, with erest. or strophinlc, attached at or near the hilum. 675. Seed 

 (suspended 1 ) of Riciuus. with its raruncle. 



PIG. 671!. Seed of White Water-I.il y, Nynijilisea odorata, in its loose and thin arillus. 



ere 



