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cuticles, so that it could be studied apart. The cast con- 

 sisted of an uncoloured substance, which partly could be 

 dissolved in hydrochloric acid, producing bubbles of gas. 

 On one side a longitudinal strap of pigment, probably an 

 indication of a former central vascular bundle, which was 

 more résistent than the surrounding tissue, was seen. The 

 cuticularisation had evidently extended to a portion of the 

 vertical cell-walls abutting on the outer skin, for the 

 network of cells is marked out *with perfect clearness on 

 the inner surface of the cuticle. The cells are arranged 

 in longitudinal rows ; their average breadth is about 50 1^ 

 the length varies from 50 to 100 f-; the transverse walls 

 are mostly placed at right angles to the longitudinal walls, 

 but sometimes oblique. My attention was drawn to a pair 

 of cells which are reniform in shape, each being half as 

 broad as an ordinary cell. This complex shows a great 

 resemblance to a stoma, but near this group there are two 

 similar but less typical groups of cells ; a third group is to 

 be seen on the right side which forms a transition over 

 to the ordinary type of cell. Perhaps this can be explained 

 as being rudimentary stomata in which the divisions of the 

 epiderjnal cells hâve taken place, but where the differen- 

 tiation has been arrested. The dark-coloured lines, which 

 separate the lumens of the cells, when examined with a 

 higher magnifying power, appeared not to be homogenous, 

 but as having a longitudinal groove. This is seen as a 

 bright line, about 1 i^- broad, running in the dark-coloured 

 band of cuticular substance. In another préparation the 

 arrangment of the cells was less regular ; in some of them 

 the cuticle was thickened in its middle part. From this 

 dark spot a longitudinal ridge runs to the adjacent cells. 

 Concerning the chemical composition of the cuticular sub- 

 stance it could be stated, that the pièces of the cuticle 

 deeply stained red with Safranine. With Sudan III after 

 heating, it took also a red colour, very évident, but some- 



