8o Worsdell . — The Structure and Morphology of the ‘ Ovule l 
given, all going to show that that writer entirely misconstrued the nature 
of the various structures which came under his notice. 
Referring to the case described by Penzig of adventitious shoots on 
ovular leaflets of Scrophidaria vernalis which bore nucelli at their apex , our 
author holds that this phenomenon arises from a coincidence of the two 
constructive forces of the two structures respectively. The shoot arises 
below the nucellus after the latter has been formed and carries it upon its 
apex ; but here no intermediate forms can exist between the two ; ‘ in all 
truly intermediate forms an homology exists between all the parts, so that 
a transformation of the same basic structure obtains.’ An analogy for 
such an enclosed apex is found in a case of Helianthus annuus , mentioned 
by Sachs, in which the normal apex was damaged. 
From all this we gather that inasmuch as no true transitional struc- 
tures between an ovule and a shoot have ever been seen, but that, on the 
contrary, all so-called ovular shoots are either axillary productions of the 
carpels or else of the nature of adventitious buds on the ovular integuments 
or the placenta, therefore the ovule can no longer be held to possess the 
morphological nature of a shoot. 
Finally, as regards the sui generis theory of the ovule, Celakovsky s 
criticism of the views of Strasburger, the chief champion of this view, are 
very instructive and illuminating. This author’s main theory, as also in 
the case of the abnormal female parts of Coniferae, with regard to the 
various virescent conditions of the ovule, is this, viz., that they represent 
the varying results of a simultaneous strife between two forces : the 
generative , tending to produce the ovule which is of the nature of a 
sporangium or emergence, and the vegetative , tending to form a leafy 
structure. Now, Celakovsky maintains that, according to this view of 
Strasburger’s, the transitional forms which occur must be those between 
two quite heterogeneous plant-organs : a leaflet or segment of a carpel on 
the one hand, and a sporangial emergence on the other ; this is, on the 
face of it, an absurdity, and represents the same fallacy as that underlying 
his position with regard to the female flower in Coniferae. For the 
transitional forms clearly betray their derivation from the self-same organ, 
their origin from the same morphological substratum. 
Moreover, the virescent phenomena clearly show that the generative 
and vegetative forces assume possession of the ovular leaflet successively 
rather than simultaneously. 
Further, ‘if the ovule is not a metamorphosis of the carpellary segment, 
but a macrosporangium, an emergence, and this purely in place of the leaf- 
segment, the ovule with its integuments should contract more and more and 
gradually vanish, the leaflet or segment, on the other hand, become more 
fully developed.’ There can be no other compromise. And yet, as has 
been repeatedly shown, this is precisely what does not happen, for the 
