DESCRIPTION OF PLATES. 



Plate I. (Frontispiece.) Valley at Secanquim. Alta Vera Paz. Guatemala, the 

 scene of experiments with weevil-resisting cotton. 



Plate II. Fig. 1. — Mature plant of Kekchi cotton, to show small size and 

 determinate habits of growth, compact foliage, and long basal branches. 

 Fig. 2. — Plant shown in figure 1, opened to show numerous large bolls and 

 habit of fruiting on basal branches. 



Plate III. Involucres of Kekchi cotton, opened to show external and internal 

 nectaries, bracts, and bractlets. (Natural size.) 



Plate IV. Fig. 1. — Involucres of Rabinal cotton, showing connate and closely 

 ■ oppressed involucral bracts. (Natural size.) Fig. 2. — Open involucres of 

 Egyptian cotton. (Natural size.) 



Plate V. Fig. 1. — Young buds of Kekchi cotton, showing numerous weevil punc- 

 tures. The buds were split in half so that the full number of punctures 

 could be seen. (Natural size.) Fig. 2. — Buds of Kekchi cotton (same as 

 fig. 1), showing successful proliferations. (Natural size.) 



Plate VI. Large buds of Kekchi cotton, the distortion indicating proliferation. 

 (Natural size.) 



Plate VII. Weevil-infested bolls of Kekchi cotton, showing larger number of 

 punctures along the middle line of the carpel, where the oil glands are 

 absent. (Natural size.) 



Plate VIII. Carpels of Kekchi cotton, showing method of proliferation. 

 (Natural size.) 



Plate IX. Fig. 1. — Kekchi cotton, successive stages of the boll. Fig. 2. — 

 Kekchi bolls (right) : King bolls (left), to show comparative size. (Re- 

 duced to about one-half natural size.) 



Plate X. Fig. 1. — Rabinal cotton, showing foliage, connate bracts, and weevil- 

 infested bolls. (Reduced.) Fig. 2. — Bolls and seeds of Kidney cotton, 

 showing oil glands and protective arrangement of lint and seeds. 

 (Reduced.) 



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