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MEMOIRS 'OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 10 



Figure 72 shows the termination of the ventral carpellary traces (below the 

 level shown). The dorsal traces turn inward as the ovary narrows into the 

 style, and only the three dorsal traces are present in the style base (fig. 73). 

 In figure 73, the ovary appears fragmented into three portions (other than the 

 style and style-appendages), and the larger triangular shapes represent the 

 ovary crests. At the next level (fig. 74) departure of stamen traces, by branching 

 from the median corolla traces, can be seen. The uppermost of the stamiuodia 

 shown terminates at this level. In figure 75, the three corolla lobes become 

 free from each other. Concomitantly with their greater widening into an 

 imbricate conformation, there is considerable ramification of veins. The upper 

 tips of two of the ovary crests may be seen at this level. The following figures 

 show the changes in vascularization of the style. In figure 76, departure of ovary 

 appendages may be seen. These appendages are recurved, so that description 

 of changes in their anatomy from departure to tip proceeds in the reverse 

 order, in terms of figure numbers. The bundles that depart into the ovary 

 appendages are branches of the three style traces, not the traces themselves. 

 One of the appendages is very short; the other two (fig. "75) show an alteration 

 in vascularization. A cylindrical organization of the bundles is attained. At 

 a lower level (fig. 74), these cylinders subdivide into several bundles, and 

 at the tip of the appendages (fig. 73) only a single bundle is present. This 

 bundle, in each, does not extend all tho way to the appendage apex. Returning 

 to the style proper (fig. 77), one may see that the three veins branch. This 

 branching continues (figs. 78-81) so that numerous vein-endings enter the 

 ultimate fringes of the stigma. Development of a central cavity in the style is 

 illustrated in figure 80. 



Variation in venation among the species of Abolboda seems to occur only 

 in the number of bundles per sepal (see above) and the relatively abundant or 

 few veins in the corolla, depending largely on corolla size. 



The question naturally arises, what interpretation of the ovary appendages 

 seems most appropriate in terms of their venation, position, and histology. 

 They cannot be regarded as equivalent to two of the three stigmas (if two are 

 present), on account of their venation. They represent, rather, branches of the 

 style bundles. The vein in each appendage does not terminate as a hydathode, 

 nor do the contents of cells in the appendage suggest a nectary function, al- 

 though this possibility should not be ruled out. The function of these structures 

 — if they cTo have any prominent function — may well be related to a pollination 

 mechanism in some way, but without further knowledge, speculations concerning 

 function would be pointless. A feature of some interest is the nature of bundles 

 in the very large ovary appendages of Orectanthe. In 0. sceptrum, the bundle 

 was observed to be large and rather diffuse, with isolated patches of xylem 

 and phloem cells. 



In respects other than numbers of veins and absence of staminodia, the 

 resemblance between Abolboda and Orectanthe flowers are close, and ovary and 

 style of Orectanthe flowers have a venation identical to that in Abolboda. 



Figs. 82-87. Achlyphila disticha, successive transections from flower. Sepals omitted in 

 figure 86, and only style base shown in figure 87. Fig. 82. Pedicel. Stippling represents thick- 

 walled sclerenchyma. Fig. 83. Departure of sepal traces. Fig. 84. Base of petals. Fig. 85. 

 Departure of stamen traces. Fig. 86. Ovary at level of ovules. Fig. 87. Style base. Vascular 

 bundles in all figures represented by circles (or modified shapes). Scale = 2 mm in 1 mm 

 divisions. 



