Z7 



a corollary that a definite morphological gradient exists in the 

 normal flower of L'lnaria: tlie upper (adaxial) stamen is sup- 

 pressed, the next two stamens are intermediate in length, and the 

 lower (abaxial) stamens are longest ; the lower lip of the corolla 

 has the greatest marginal hypertrophy (as shown by its refolded 

 labium) and it is also from the middle of its three segments that 

 the spur is produced. Obviously it is this abaxial segment of 

 the developing flower primordium which is normally most active, 

 both physiologically and ontogenetically. Also it is in (or on struc- 

 tures produced by) this region where we find the greatest number 

 of abnormalities which, in the final analysis, are only visible proofs 

 of unusual physiological activities resulting in abnormal morpho- 

 logical structures. 



Of further interest was a series of specimens collected by John 

 McCallum, near Morris Park, Long Island, in 1912. It involved a 

 series of plants exhibiting several types of peloria, including both 

 spurless and multiple-spurred forms. Of these we will consider 

 only one flower (Figures 15a-c). Here the spur was absent; also 

 there was good evidence that the middle segment of the lower lip of 

 the corolla had been lost, each lip, therefore, consisting of two 

 corolla segments. Substantiating the view that one entire segment 

 of the flower was lacking was the fact that the calyx had but four 

 segments, with no evidence of fusion between lobes ; also the flower 

 bore but three stamens. When one compares the diagram of this 

 flower (Figure 15c) with that of a normal flower (10b), it is 

 obvious that, in addition to one sepal and one corolla segment, 

 one of the abaxial stamens had been lost. Thus, there was achieved 

 an essentially tetramerous flower modified only by its inherent 

 zygomorphy, and this evident by a residual bilabiate condition. 



Going outside the Torrey Club Area for material, we have a 

 series of plants collected by William Scott at York Mills, near 

 Toronto, Canada, September 18, 1911. Judged only by the flowers, 

 this material could by no stretch of definition be placed in the 

 genus Linaria, although there was no mistaking the plant's habit. 

 The flowers were almost completely regular, with four sepals, four 

 corolla segments, two anthers and a two-carpelled ovary (Figures 

 16a-c). The collector's notes state that it "grows in great pro- 

 fusion in at least four localities within about five miles of Toronto. 

 .... I think it does not set seeds but propagates itself simply from 



