Floral Abnormalities- 35 



The normal flower of E. obovalis has five somewhat strap- 

 shaped petals, which are always fully expanded, exposing the two* 

 wiiorls of stamens to view. (Plate III., Fig. 3.) 



The typical abnormal flower also has five petals, similar in 

 colour to the normal ; these, however, never become fully ex- 

 panded, but remain more or less erect, partially blotting the 

 stamens from view. Each petal has a distinctly waved outline,, 

 and the tip of the lamina Is generally incurved, forming a little 

 hood, as it were, around the anther, which is situated a little above 

 the middle line, on its ventral surface. No other change is notice- 

 able, the sepals, stamens, and carpels being the number charac- 

 teristic of the genus. (Plate III., Fig. 2.) 



An extreme type of abnormal flower, and one of far less fre- 

 quent occurrence is figured on Plate III., Fig. 4. In this case the 

 lamina of each petal is modified to form a narrow filament-like 

 structure, with a small expanded distal portion on which the 

 anther is placed. It has been found, as is shown in Text figure 

 1, that the degree of reduction of the petal is dependent upon the 

 simplicity or complexity of the anther it bears. The complex 

 anthers here present will therefore account for the extreme modi- 

 fication of the petals, to such an extent that the latter are hardly 

 distinguishable from true stamens. This resemblance is further 

 emphasised by the presence of short hairs on the filamentous por- 

 tion of lamina, similar, to those present on the staminal filaments. 



Structure of the Anther. 



For the examination of the structure of the petal and anther r 

 microtome sections were used, all of which were stained with 

 Delafield's Haematoxylon. Petals from unopened buds have been 

 used both for this purpose, and for. the examination of 'the form 

 of the anther and its relation to petal. This was done principally 

 to facilitate obtaining complete drawings with the camera lucida r 

 under a low power of the microscope, but also because of the 

 greater abundance of buds than opened flowers in the material. 



The anther is very variable in form and structure — as all 

 gradations are met with, from the simple unilocular to the com- 

 plex quadrilocular condition. These stages are shown in Text 

 figure 1, and may be summarised as follows: — 



