62 WorsdelL— The Structure and Morphotogy of the 'Ovule! 
Payer (23), in his great work on the organogeny of the flower, evi- 
dently — at least, in certain cases — regards the ovule, although he nowhere 
explicitly states it, as the morphological equivalent of a portion of the axis, 
this being the view definitely entertained by him with regard to all placental 
structures. In describing the development of the ovary in the Polygonaceae 
he says : ‘ At the bottom of this cup [the depression arising between the 
developing carpels] the apex of the axis is observed, which becomes suc- 
cessively clothed with two envelopes, thus constituting an erect and ortho- 
tropous ovule.’ He applies the same interpre- 
tation to the nature of the ovule in Urticaceae, 
Chenopodiaceae, Paronychieae, and Amaran- 
taceae. 
Magnus (44) offers a precisely similar ex- 
planation of the ovule, terminal to the axis, 
in Najas. 
These two latter authors may be regarded as 
typical examples of those who, in their endeavours 
to determine the morphological value of any given 
organ are primarily influenced by the position in 
which it arises on the plant. Hence we may 
speak of such as topical morphologists. 
The well-known observations made by 
Peyritsch on abnormal structures in the ovaries of Cruciferae and other 
plants will be referred to more fully hereafter. 
Penzig (57) examined proliferated ovules of Scrophularia vernalis L. f 
which he found, in the extreme metamorphosed condition, were toothed 
leaflets bearing a nucellus at different levels on their upper surfaces or apex. 
He also found nucelli borne at the apex of elongated structures growing on 
the placenta which were often fused with the leaflet on the dorsal side ; 
the appearance of the bundle in the nucellus showed the latter to be of 
ovular nature. He came to the conclusion that such phenomena are in 
greatest harmony with the bud-theory of the ovule. 
Many other authors have put forward this theory of the ovule, 
reference to whose works will be found in the subjoined bibliography. 
A discussion of the validity of the axial-theory will be deferred until 
Celakovsky’s views on the whole subject are brought forward. 
We have next to notice that which we have termed the sui generis 
theory of the ovule ; in this connexion there are the writings of four or 
five botanists to be taken into account. 
Schmitz (43), in his study of floral development in the Piperaceae, and 
especially of Peperomia repens , makes this general remark : that ‘ as the 
ovule arises sometimes as an emergence on a leaf, and sometimes by meta- 
morphosis of the vegetative apex, its relation to the shoot as a whole 
Fig. 4. Portion of flower 
of Polygonum , showing both 
ovary and ovule terminal to 
the axis (after Payer). 
