(u) Stamens, collectively termed the Androeoium : 



(ft) Carpels, collectively constituting the Gynoecium ; as special regions of 

 the floral system. 



In higher floral types, some of the original androecial members are adapted as 

 coloured laminae (petals of the corolla) , and the outer perianth-members are then 

 distinguished as the sepals of the calyx. 



The corolla-petals are normally ' coloured ' (other than green) ; as the sepals are 

 normally green, but not invariably so ; the coloured condition may be distinguished 

 as ' petaloid ', in calyx or perianth. 



Symmetry of the construction, primarily centric (Radial, Regular, Actino- 

 morphic) ; in specialized types eccentric (Irregular, Dorsiventral, Zygomorphic). In 

 extreme cases such zygomorphic flowers are orientated with the vertical, geotropically, 

 in correlation with visitation by similarly orientated insects, as Bees. 



Arrangement of Parts follows phyllotaxis-patterns ; spiral or more commonly 

 whorled, giving precise mechanisms ; but complex, and combinations of spiral and 

 whorled in same flower ; low numbers 2, 3, 5 prevail (4 and 6 as variants on 5) : cf. 

 dimery, trimery. pentamery, &c. 



Secondary Complications with wide range : as by secondary growth-zones 

 (intercalary extensions) affecting groups of members : 



(a) cf. gamophylly, gamosepaly, gamopetaly, staminal tube, syncarpy : 



(ft) or individual members ; cf. petal ' claws ', stamen ' filaments ', style : 



(y) Special case of complex ovary-formations, with types of ' placentation '. 



Normal acropetal production of members on an abbreviated conoidal receptacle 

 gives the case of Hypogyny, and the c Superior ovary ' of older writers. 



A hollowed or crateriform apex may drop the terminal gynoecium below the 

 level of the outer members (Perigyny): the ovary-cavity may be involved in later 

 extension as a state of Epigyny, with ' Inferior ovary '. 



Colour-effects, due to residual pigments of the chlorophyll-apparatus acquiring 

 new functions, as attraction of insects ; mainly due to : 



Carotin, yellows and reds, pigment in plastids (Carrot, Buttercup). 

 ) Anthocyan, purple-reds, violet, and blue, soluble in cell-sap (cf. Beetroot, 

 Copper-Beech). 



(y) White flowers by total elimination of all pigments, and air-films in tissues. 



A colour-contrast is more generally aimed at, rather than any special tint. 



Reduction-effects : Whether due to decadence or specialization, imply loss of 

 parts : e. g. aphylly, apetaly, dicliny (monoecious, dioecious), ' neuter ' flowers. The 

 limiting case of a flower may be a staminate flower reduced to one stamen: or 

 a carpellary flower reduced to one carpel ; or two carpels, syncarpous, including one 

 ovule. 



Time factors : involving co-ordination of growth-rates and movements in dif- 

 ferent parts of the mechanism : Sequence of Events ; Bud-expansion ; Final adjust- 

 ments ; Closing-movements ; Proterandry, protogyny ; Daily period ; Shedding of 

 parts by abscission. 



Tabulation and schedule of Form-Factors. 



(1) Floral formula, meagre method, in various types and symbols, e.g.: 



S, 51 P, 5; A, 5 + 5; G(s). 



(2) Floral diagram, as conventional ground-plan ; useful for whorled flowers 

 with few parts ; based on bud-sections : 



Orientation, on 2 axes at right angles, with Median (Antero-Posterior) 

 plane, Transverse plane, Diagonal planes : the subtending bract (anterior) ; 

 the parent axis (posterior) ; prophylls (lateral). 



Representation of parts : conventionalized transverse sections of leaf- 

 members (sepals and petals) ; of anthers, in androecium ; and transv. sect. 

 of ovary (low power), for gynoecium. 



Accessor}* details as nectary-glands ; prefloration, quincuncial, valvate, 

 convolute ; stigmas, spurs, bilaterality and plane of zygomorphy. 



(3) Sectional Elevation, as scale-drawing of half the mechanism, and cut in 

 given direction ; commonly in median plane (P to A), and constructed in 

 all detail to scale (e.g. X 10): finished figure in accurate colour-scheme: 

 similar constructions for different phases of complex mechanism. 



M 

 (ft) 



