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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[vol. 10 



Epidermal Relief. 



In Abolboda, both corolla (fig. 92) and ovary exhibit epidermal relief. Such 

 relief occurs on both surfaces of the corolla lobes. The formation is not 

 merely a cuticular relief. The epidermal wall is raised into delicate, ridged 

 eminences which run, predominantly, in a longitudinal direction on the organ 

 concerned. These eminences are particularly prominent above radial walls of 

 epidermal cells. The cuticle follows outlines of the epidermal cell-wall relief. 

 Outlines of the cuticle, therefore, are parallel to those of the wall relief, but less 

 detailed. 



In Orcctanthe sceptrum snbsp. occidentalis (fig. 91), similar ridges were 

 observed on the epidermis of corolla lobes, but they are much coarser and less 

 detailed than those of Abolboda Unearifolia. On the ovary, virtually no relief 

 occurs. 



On petals of Achlyphila d/isticha (fig. 93), no appreciable relief could be 

 detected on epidermal cells. On the ovary, however, there are forms of epidermal 

 cell relief which correspond closely with those of Abolboda linear if oli a. Cuticular 

 relief thus suggests similarity between the two genera. 



Anthers. 



The anthers in the three genera offer distinctive points of comparison. In 

 Abolboda (e.g., A. linearifolia, fig. 88), the connective is wide but thin. Between 

 the veins and the anther sacs, the mesophyll of the connective is spongy. The 

 endothecium is a single layer of cells wide. In Orcctanthe sceptrum subsp. occi- 

 dentalis (fig. 89) the connective is rounded. The endothecium is a single layer 

 of cells wide except at the portions of the anther sacs nearest the connective. 

 The endothecial cells are large, and the thickening bands are narrow. The 

 anthers of Achlyphila (fig. 90) have a connective narrowed at their contact with 

 the anther sacs. The connective itself is relatively narrow. The endothecium 

 is a single of cells wide except where it is adjacent to the connective. Thicken- 

 ings on endothecial cells are relatively wide compared with those of Orcctanthe 

 and even Abolboda. Mention should be made of the conspicuous epidermal relief 

 that occurs on the surfaces of the anther sacs. This feature offers a further point 

 of comparison between Achlyphila and other Xyridaceae. 



Ovary Crests. 



The ovary crests of Abolboda, a characteristic of that genus, consist of large 

 lignified cells. This is shown for A. sprucei in fig. 38. 



Capsule Wall. 



Mature capsule valves were available only in Abolboda and Orcctanthe. As 

 shown for A. macrostachya var. angustior (fig. 104) capsule valves in Abolboda 

 consist of thick-walled sclerenchyma. Cells at the points where loculicidal 

 dehiscence occurs are small and non-lignified. Likewise, the septa are not lig- 

 nified, at least in their inner portions, and lignification is likewise absent where 

 the valves are joined to the ovary base. The epidermal cells may be somewhat 

 radially elongate, especially opposite the septa. In the fruits of Orectanthe 

 (fig. 105) on the contrary, lignification even in mature fruits is mostly limited 

 to the epidermal layer. Cells in this layer are mostly markedly elongate radially 

 and sclerified. 



