1889.] BOTANICAL GAZETTE, 79 



tively thick, and shows no tendency to thin out where it bor- 

 ders upon the cuticular layers. In this it resembles the con- 

 dition in Pinus, and differs from that found in the under sur- 

 face of the leaf of Taxus baccata, in which the non-cuticu- 

 larized layers are scarcely to be detected where they border 

 upon the cuticular. 8 



The cuticularized portions follow the outer surface of the 

 epidermal cells and project inward in somewhat sharply- 

 pointed conical form. Jn many instances the cuticular layer 

 is largely developed at the stomatic furrow, although as a 



rule this may not hold. 



The epidermal cells contain nothing further than the char- 

 acteristic contents of such cells, although in the cuticular 

 layers are found thickly massed granules, presumably cal- 

 cium oxalate, as treatment with acetic acid produced no 

 effect, and as this substance is not uncommon in the Cupres- 

 sinese. 9 No crystalline forms were found, and although the 

 substance was present in comparatively large quantities, no 

 modification in the coloration of the epidermis could be de- 

 tected. The walls of the epidermal cells, especially the 

 inner ones, are extremely irregular and show numerous in- 

 foldings, which in some instances are very prominent. There 

 seems to be no special order in their disposition, either as 

 regards the individual cell or the other tissues of the leaf, 

 although the larger forms are more frequently found in the 

 region of the resin duct than elsewhere. It is also possible 

 that those of the inner leaf surface may be more prominent 

 than those of the outer. The purpose of these infoldings 1 

 have been utterly unable to determine, their irregular ar- 

 rangement and development negativing every conjecture. 

 In view of some facts to be presented later in this paper, it is 

 at least within the range of possibility that they serve for 



purposes of support. 



A median vertical longitudinal section illustrates still 



further these points (fig. 10). The apex of the leaf is formed 

 by a continuation of the epidermal cells of the inner surface, 

 the apical cell being of this series. The two cells immedi- 

 ately adjoining the apical cell of both the outer and inner 

 surface are in immediate contact, no parenchyma interven- 

 ing. Those of the outer surface are much modified in form, 

 while those of the inner retain their normal shape. At the 

 third cell from the apical cell, there occurs a peculiar modi- 

 fication, due either to the pre sence of extremely short 



Bary, Comparative Anatomy of Phanerogams and Ferns, p. 77. 

 Bary, I. c. , p. 10J. 



