THE GYNCECEUM (. DESCRIPTION ) 83 
(this is the most common case), amphitropons , when the funicle is 
attached to the middle of the ovule, forming a T, also a common case, 
campylotropous , when the ovule itself is curved into a U shape so as to 
bring micropyle and chalaza side by side, as in Cruciferae, &c. Whether 
the raphe is upwards or downwards (Fig. 5, A, B), dorsal (away from the 
centre) or ventral (on the side next the centre or the flower, Fig. 5, C), is 
often of much taxonomic importance. 
The Floral Diagram is a most useful method of 
expressing many of the important features in the morphology 
of the flower. It represents an imaginary section through 
the bud, taken (if such were possible) so as to pass through 
the ovary and anthers, and through the parts of the perianth 
where the aestivation is most clearly shown. With the 
exception of the hypogyny or epigyny, the diagram shows 
most of the characters that are usually necessary for identi- 
fying the natural order, and hence is of much use in 
classification. A number of diagrams are given in Part II. 
and should be carefully compared with the flowers them- 
selves. The diagram may also be used ( cf. Polygonaceae in 
Part II.) to express theoretical views as to multiplication or 
suppression of organs, &c. 
In drawing a floral diagram we put in at the top the 
original stem upon which the flower is a branch, and at the 
bottom the bract, to mark the orientation. Upon the axis 
of the flower itself there are usually one or two bracteoles, 
as we have seen. The parts of the flower usually follow 
certain definite rules in their orientation to the bracts and 
bracteoles. Only the calyx need be considered, as the inner 
whorls have their arrangement determined by the outer. 
Whilst, as we have seen, the parts of the flower are usually 
condensed into whorls, the calyx most commonly develops 
in a spiral way, the sepals appearing in consecutive order 
rather than simultaneously. The general rule, to which 
however there are frequent exceptions, in the formation 
of new organs at the growing point, is that each organ 
develops in the widest space left between its immediate 
predecessors. The position of the bracteoles illustrates this. 
When there is one posterior bracteole the parts of the flower 
are usually three in each whorl and the odd (first) sepal is 
anterior, as e.g. in Zingiberaceae {q.v.). With two bracteoles 
and three sepals the first sepal lies nearly opposite the upper 
bracteole and the odd sepal is median (either anterior or 
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