REPRODUCTIVE APPENDAGES. CHAP. IV. 



this case it invests the seed wholly, and is hence 

 said to be complete ; but in others, as in Cdastrus, 

 it invests it only in part, and is hence said to be 

 dimidiate ; in Dictamnus Fraxinella, it is said to 

 invest two seeds. It is generally of a membra- 

 naceous or leathery sort of contexture, but in the 

 genus Evonymus it is somewhat succulent ; and in 

 a few species of Orchis it resembles a finely reti- 

 culated web. In the genus Oxalis it is membra- 

 naceous and elastic, ejecting the ripe seed with con- 

 siderable force.* 



Of the The mace which envelopes the pericarp of the 

 meg ' nutmeg, so much esteemed for its delicate flavour 

 and relish, is generally regarded by botanists as an 

 aril ; and the envelope of the seed of the carex, 

 which Linnaeus calls the nectary, is by Dr. Smith 

 transferred to the head of the aril also. But if the 

 foregoing definition is correct, and it includes, as 

 I think, the essential characters of the aril, as de- 

 fined both by Linnseus^ and Gaertncr ^ as well as 

 by Dr. Smith himself, then it follows that the 

 two above-mentioned organs are improperly deno- 

 minated arils, as including not only the seed but 

 also the ovary, in which, according to the definition, 



* Smith's Introd. p. 297. 



t Arillus, tunica propria exterior seminis, sponte secedens. 

 Phil. Bot. sect. 86. 



t De Seminibus. Introd. 



Arillus, the tunic, is either a complete or partial covering of 

 a seed fixed to its base only, and more or less loosely or closely 

 enveloping its other parts. Introduction, p. 296. 



