DESCRIPTION OF PLATES. 



Plate I. Abnormal branches and involucres in the Dale variety of Egyptian 

 cotton, where such abnormalities are especially common, though they occur 

 also in other Egyptian varieties, as well as in Upland cotton. The figure 

 near the upper left-hand corner of the plate represents a normal involucre 

 of Egyptian cotton seen from the side, so that only one of the three bracts 

 is shown. The figure at the top of the plate and that with the largest leaf 

 immediately below represent the first stages of transformation from leaves 

 to bracts, with the stipules enlarged, the petiole shortened, and the blade 

 reduced in size, but retaining the texture of a normal leaf. Other figures 

 show intermediate conditions, with the petiole suppressed, the blade more 

 reduced and united with the stipules, and the texture becoming the same 

 as in an ordinary involucral bract. The lower right-hand figure shows an 

 involucre with only two bracts, the upper bract still of the intermediate 

 form, while the lower is nearly normal, except at the base, where there is 

 an unusually large bractlet. (Natural size.) 



Plate II. Bolls produced on short axillary branches of the Dale variety of 

 Egyptian cotton. The long stalks of these bolls represent the fused joints 

 of rudimentary branches, as shown by the presence of small bractlike leaves 

 and stipules. In the figure on the left-hand side of the plate there is a 

 bractlike organ in the position that would be occupied by a leaf on a normal 

 fruiting branch. In the figure at the bottom of the page this organ is re- 

 duced to the size of a stipule, while on other stalks it is entirely absent. 

 One stalk is distinctly jointed and bears two bolls in a double involucre, an 

 example of fasciation. The right-hand figure shows an abortive fruiting 

 branch ending in a single leaf with enlarged stipules, and a simple axillary 

 branch bearing a normal boll. (Natural size.) 



Plate III. Part of a Maragogipe coffee tree on the Sepacuite plantation, Alta 

 Vera Paz, Guatemala, showing three upright branches bearing numerous 

 horizontal lateral branches. The leaves of this variety are larger, heavier, 

 and more inclined to be crumpled than those of the ordinary Arabian coffee. 

 (Greatly reduced.) 



Plate IV. The left-hand figure shows one internode of a very young upright 

 and a complete internode of one of its lateral branches, projecting under- 

 neath the right-hand figure. The right-hand figure shows an older upright 

 where pruning has forced the growth of two new upright brandies, with 

 short basal internodes, arising below the bases of the nearly horizontal 

 lateral branches. (Natural size.) 



Plate V. A diseased condition of the lateral branches of Arabian coffee in 

 eastern Guatemala, where the branching of the laterals has been forced by 

 persistent pruning. (Natural size.) 



Plate VI. A young cacao tree on the Trece Aguas plantation, Alta Vera Paz, 

 Guatemala, showing the normal method of producing branches in whorls.- 

 The whorled branches do not give rise to upright shoots, which develop 

 from the side of the old uprights underneath the whorls. (Greatly reduced.) 



Plate VII. Fig. 1. — Petioles of leaves from uprights of cacao. The upright 

 branches of the cacao produce leaves with the long petioles (left-hand side 

 of the figure). The whorled branches produce leaves with short petioles 

 (right-hand side of the figure). (Natural size.) Fig. 2.— Section through 

 the rhizome of a banana plant showing that sword suckers are true 

 branches of the rhizome, unlike the broad-leaved suckers that arise from 

 buds near the surface of the ground. (Greatly reduced.) 



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