254 NATURAL HISTORY OF PLANTS. 



\i\^ to false interseminal septa. — This character was formerly used 

 to separate genera ; it can be so used no longer. We have passed 

 the day when the Unofias were all supposed to present these con- 

 tractions, then thought to be always absent in Uvaria ; for in certain 

 of the latter there are more evident marks of dissepiments than in 

 some of the former, and these again may have their fruit with 

 the surface quite smooth and "continuous." The genua J la /j::f'h'n 

 (A. DC), that was said to be distinguished' by its fruits, " here and 

 there irregularly swollen," like those Unonas that have irregularly 

 moniliform berries, is at present by all included in Xylopia ; and 

 hardly is this cliaracter thought sufficient to characterize sub-genera 

 in certain genera. 



12. The aril. — As we know the origin of the true aril in A/ionacrtp, 

 we can conceive a priori how this organ, formerly thought so very 

 important, can have no real taxonomic value. The soft layer sur- 

 rounding the coriaceous seed-coat, which is thickened throughout 

 in Mat/noIiacccB, in Anonacea only undergoes this thickening around 

 or over the hilum or micropyle, in their interval, or on the sides of 

 the seed. This sort of hypertrophy may even escape notice on a 

 superficial observation, especially in the dry seed, and when it is 

 limited to a small cord bounding the two former regions. The seed 

 has then been described as wanting an aril, though this organ is 

 still represented, for its form and size can have no absolute value. 

 Never have we thought it possible to give a generic value to the 

 character of the presence of the aril." 



13. The glandular dots scattered over the surface of the leaves 

 and some other organs. — This fact and its results, as regards the 

 aromatic properties of the JnonacefC, appear to possess some im- 

 portance in certain genera ; for some consist wholly of inodorous 

 species without dots. But here again we have nothing absolute, for 

 in so natural a genus as Anona some species arc dotted and others 

 are n<jt. 



14. Tlie inflorescence. — It is, I think, no longer possible to found 

 genera in Anonacofp on the situation and grouping of the flowers. 



' A. DC, Mim., 9. ollcii wwd hy iimn." Ht-rc it would •ocm he 



' TliiH wiu» not the opinion of A. de Can- cdnfusiH tho aril and tlio jHTit-nrp it«olf. Ac- 



l)OLl.E (Mem., 8), who moreover ntated that llio eorilinh' t<i the wnue author (1. a), at the time 



aril, " when prcMent, •ocreten iin apparently reHi- ho wrote, no Aniatie AnonuU with u clearly arilbto 



iiouH urouiatic Huhblaiice at the hiwe of the M-ed*. (teed wan known. 



