ANONACE^. 



189 



imbricated in the bud, and finally valvate. The inner petals are 

 smaller, and alternate with these, and like them are imbricated 

 when young. When the flower is fully expanded they do 

 not even touch on a level with their contracted bases.' The 

 stamens, very numerous and spirally arranged, are of the shape of 

 an elongated wedge inserted into the receptacle by its apex, and 

 swelling above into a rounded head (figs. 223, 224). The anther 

 consists of two narrow cells applied vertically along this wedge, 

 close to its edges, but nearer the outer face. These extrorse cells 

 dehisce longitudinally." The gynseceum consists either of six free 

 carpels superposed to the petals, or more frequently of some other 

 number.^ Each consists of a unilocular ovary, bearing a short 

 recurved style, covered with stigmatic papilla?.^ Within the ovary 

 we find a parietal placenta divided by a longitudinal groove^ into two 

 vertical lobes, each of which supports a row of anatropous ovules,'^ 

 with the raphes looking towards those of the other row. The fruits 



^ These petals preseut several peculiarities 

 which we have pointed out in a note entitled Ob- 

 servations sur des Petales ci Structure Anormale, 

 {Adansonia, vi. 253). The chief are the fleshy 

 glandular projections of the inner fiice, secreting 

 a nectar which retains the pollen that falls 

 into the cup of the corolla ; the fact that these 

 papillse contain ti'achea3 which proceed from 

 the fibrovascular bundles of the limb, formin<j 

 short masses, ending in spirally thickened cells 

 placed almost end to end. When young tlie 

 petals are quite green ; they gradually acquire a 

 brownish tint, which grows deeper day by day, 

 finally becoming a very dark wine purple — a 

 colour often found in the corollas of Anonacea:. 

 It may be replaced by yellow or orange, or even 

 by brilliant red, rarely, as in U. {^Sapranthus) 

 nicaraguensis, by violet, or even nearly blue 

 tints. 



^ The stamens, often formed on this type in 

 the order Anonacece, and, especially in the genus 

 Uvaria, are of the kind which Bentham & 

 HoOKEE term " Stamina Uvariearum." The 

 sort of inverted truncated pyramid formed by 

 them varies greatly in length at different ages, 

 as does that part of the stamen below the cells, 

 which is called the filament, though not really 

 distinct from the connective. The base becomes 

 early detached, and they fall into the cup of tlie 

 corolla, but still remain some time attaclicd to 

 tlie receptacle by bundles of trachea3, which 

 gradually elongate like those supporting the 

 seeds of Marjiiolia. The pollen in eacli cell forms 

 like a long necklace of two or three rows of white 



grains united by the very thin debris of the 

 mother-cells. Each grain consists of from two 

 to four (usually three) ellipsoidal granules. These 

 are gUibrous, with a minutely areolate outer mem- 

 brane, and are the simple grains. When three 

 of these cohere they occupy the vertices of an 

 equilateral triangle ; when four, tliey form a 

 regular or irregular tetrahedron, as in Drimi/s. 

 On moistening the pollen the depressions sepa- 

 rating the elementary granules tend to become 

 obliterated. 



^ There are often only three, or sometimes 

 even two, c:irpels. 



'* The stigmatiferous part is obovate, white, 

 and very soft. The rounded apex is somewhat 

 reilexed and bathed in a viscid licjuid at the time 

 of impregnation. Later on the whole stylar por- 

 tion of the ovary blackens and separates by its 

 now very contracted base, from the apex of the 

 ovary, which remains deep green, and is entirely 

 covered with small white hairs. 



^ This groove is as well marked without as 

 within the carpellary leaf, along the whole length 

 of the internal angle of the ovary, and is prolonged 

 on to the style, its thickened and everted borders 

 forming the stigmatic surface. This also extends 

 a little without the apex of the style. 



'' Tlieir number varies greatly. There may be 

 as many as fifteen in each row. They are in- 

 completely anatropous. They have two coats, 

 of which the inner is very remarkable for tiie 

 long tube wiiich it sends through the exostonie; 

 the wall of the endostomic orifice is swollen into 

 a rinir at the end of this fuimel. 



