166 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, 1890. 



slightly thickened sub- globose facetted part of the stalk that the 

 florets are attached. The individual florets do not possess special 

 stalklets. So much of the structure of the normal inflorescence it is 

 necessary to detail in order to make the conditions in the diseased 

 flowers intelligible. 



In the diseased flowers a ring of florets makes its appearance in 

 the axils of the bracts near the middle of the stalk that are normally 

 sterile. The thickened end parts of the stalk that are normally short 

 and globose become elongated in such a manner as to transform the 

 globular flower head into a cylindric spike on which the florets in- 

 stead of being crowded together are arranged at short intervals from 

 each other. At the same time each of the florets developes a short- 

 special stalklot, and in place of all the florets opening simultaneously 

 as they do in the normal flower-heads, those florets in the diseased 

 spikes that are nearest to their apices are smaller in size and later 

 of growth than those below them. It ought to be noticed that even 

 in fruit there is no tendency in undiseased plants to elongation of 

 the part of the stalk to which the pods are attached, and no disposi- 

 tion on the part of the pods to ripen more quickly at the outside of 

 the branch than in the centre. At the same 'time it has to be repeat- 

 ed that it is entirely owing to special elongation of this part of the 

 stalk in diseased flowers that the flower-head becomes changed from 

 a ball into a spike, because the interval that in normal flower-stalks 

 exists between the barren bracts and the flower- heads themselves 

 still continues to exist, destitute of florets, between the circle of florets 

 that appears abnormally in the axils of the bracts and the basal 

 florets of the cylindric spike. This interval which in undiseased 

 flowers is 5 — 6 mm. long, measures 10 — 12 mm. in diseased ones. But, 

 the increase in length of this part is merely due to the general 

 hypertroplry produced by the disease, and it is not its size but its 

 existence at all in the diseased flower that is of interest. 



Expressed in technical teratological language the conditions in- 

 duced by the disease are : — Increase in the size of the parts affected 

 by general hypertrophy, with some alteration of shape by distortion 

 combined with conversion of florets from sessile to pedicellate by 

 elongation, conversion of a capitate inflorescence into a spike by 



ostasis, change of a simultaneous and therefore at least sub-definite 



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