MACROSCOPIC AND MICROSCOPIC CHARACTERS OF PLANTS. 



825 



which contain only orange-brown chromoplasts, and to 

 hairs which in some instances are filled with a lavender 

 cell sap, and in others have deep orange-brown chromo- 

 plasts. In C. villosum it is pale brownish-greenish- 

 violet, due to many cells being filled with lavender sap 

 and yellow chromoplasts and a few having yellow chromo- 

 plasts only, and to many hairs that contain a pale-violet 

 sap with yellow chromoplasts, and a few that have only 

 orange or brown chromoplasts. In C. lathamianum the 

 color is dark greenish-purple, due to the cells being filled 

 with a deeper lavender cell sap than in C. villosum 

 together with yellow chromoplasts, and hairs filled with 

 yellow chromoplasts only, and also those with yellow 

 chromoplasts and a violet sap. In C. lathamianum in- 

 versum the background is orange with reddish-brown 

 spots and veins, due to a deeper violet sap than in 0. 

 lathamianum, together with yellow chromoplasts in 

 nearly all the cells and to hairs which contain yellow or 

 brown chromoplasts. 



Sections of the lower epidermis of the labellum were 

 taken at a point between the apex and the most anterior 

 part (between the top of the slipper and the toe). The 

 cells are large and have very wavy walls. They are 

 smaller in C. spicerianum than in C villosum, and larger 

 in both hybrids than in either parent, except in C. latham- 

 ianum in which the width is identical with that of C. 

 villosum. (Table J 55.) 



The color of this region in C. spicerianum is greenish 

 brown, due to yellow chromoplasts and a lavender cell 

 sap in the cells. In C. villostim it is brownish green with 

 brownish- violet veins, due to cells which may contain 

 yellow chromoplasts only, and to others which have both 

 yellow chromoplasts and a pale-lavender sap. In C. 

 lathamianum it is more like an olive-green with faintly 

 brownish veins, due to the lavender cell sap being less 

 prominent and the yellow chromoplasts more prominent. 

 In C. lathamianum inversum it is more of a greenish 

 orange, the yellow being more prominent than in C. 

 lathamianum. TTnder the microscope there appears to 

 be no violet sap, the color being due solely to deep-yellow 

 chromoplasts. 



Sections of the lower epidermis of the labellum were 

 also taken at the very base along the median line. The 



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