256 NATUIiAL HISTORY OF PLANTS. 



From tills i^roup we shall first, simply from practical considerations, 

 an<l not losing sis^ht of the artificial character of the proceeding,' take 

 tliose A/ionacccP which appear to possess two calyces and one corolla. 

 Tiie other series, on the contrary, contains those with two corollas 

 and one calyx.- 



Serics of the Miliuse.e. — Gynteceum polycarpous. Perianth triple 

 liypogynous. ^liddle perianth more like the outer than the inner. 



Scries of the Anone.t^.. — Gyna3ceum and receptacle of the preceding ; 

 middle perianth (outer corolla) more like the inner than the outer 

 (calyx). "We have seen that this series is then subdivided according 

 to the conformation of the corolla into five sub-series, as follows : — 

 1. th-ariece ; 2. XJnonece ; ?>. Xjjlopiea ; 4:. RoUiniece ; 5. O.Tymitrea.^ 



The Anojiacea present great uniformity in the general characters 

 of their vegetative organs. We always find non-herbaceous plants 

 with alternate exstipulate leaves, varying greatly, it is true, in 

 the size, consistency, and duration of the parts. The stem is 

 almost always aerial ; in Enpomatia Bennettii alone there is a rhizome 

 creeping nearly horizontally below ground, and bearing the aerial 

 branches. The arborescent Anonacea are nowhere stated to attain to 

 any great size. The largest trunks in any collection are about as thick 

 as a man's thigh. There are in this order a large number of shrubs 

 or little bushes which divide into fascicled branches from the level 

 of the ground ; and in very many exotic species we find this arrange- 

 ment so well shown in our cultivated Asimina triloba. Often, again, 

 the stems or slender branches of the AnonacecB twine round neigh- 

 bouring objects, and many species are described as creepers or 

 climbers. Has this peculiarity any influence on the anatomical 

 structure of the stem ? We must answer in the negative, but only 

 as regards those species wx have had the opportunity of studying. 

 Except a rarefication of the cortical parenchyma, to form spaces in 

 the centre of the masses of cellular tissue between the rows of liber 

 bundles, we have found the same structure in the branches of the 

 climbing and in the non-sarmentose species of Anona, Unona, and 



' See J'Mhm)i»(7, viii. 309. based arc, with one exception, those used by 



^ Except when one corolla disappears. It is Bf.ntuam & Hooker, the only difference being 



usually the inner one; in Enantia alone is the the relative importance assigned to these groups ; 



outer corolla absent. But in all these plants there for we term sub-series what they have called 



are only three sepaloid leaves. tribes. 

 ' The characters on which these divisions are 



