JOM£ OF AGRIOITIIAL ISEARCH 



Vol. XIII Washington, D. C, May 13, 1918 No. 7 



CHEMISTRY OF THE COTTON PLANT, WITH SPECIAL 

 REFERENCE TO UPLAND COTTON^ 



By Arno ViEHOEVER, Pharmacognosy Laboratory, and Lewis H. ChERNOFP and '-IBVaj^. 

 Carl O. Johns, Protein Investigation Laboratory, Bureau of Chemistry, United ^''^W' ■,,,,, 

 States Department of Agriculture ^*-^Ia\i 



THE PROBLEM ^^'^'^^tiOi^ 



The main purpose of the investigation reported in this paper was to 

 isolate the substance which proves so attractive to the boll weevil, an 

 attraction causing such disastrous losses to the cotton industry.^ While 

 this paper chiefly concerns the isolation of the glucosids and their prod- 

 ucts of hydrolysis, preliminary studies of an ethereal oil which has been 

 isolated from different parts of the cotton plant are also discussed. 

 This oil has been found decidedly attractive to the boll weevil. 



It was deemed important, furthermore, to ascertain whether or not 

 cotton (Gossypium spp.) grown in this country, and especially the Upland 

 species (Gossypium hirsutum), contained any substances isolated pre- 

 viously by Perkin from Indian or Egyptian types. Since results of the 

 writers brought out the fact that Upland cotton was different in chemical 

 composition from any of those previously investigated by Perkin, it was 

 considered advisable to report briefly his work on the chemistry of other 

 types of cotton. These investigations, it is hoped, will emphasize the 

 importance of establishing definitely the type of cotton used in any 

 further work. 



I.— THE GLUCOSIDS AND THEIR PRODUCTS OF HYDROLYSIS 



During the course of his investigations Perkin (4) ^ found that the 

 white flowers of Indian cotton (G. neglectuvi var. roseumy were devoid of 

 dyeing properties, and the pink flowers of G. sanguineum contained 

 only traces of a coloring substance, probably quercetin. The flowers of 

 Egyptian cotton, the yellow flowers of common Indian cotton (G. her- 

 baceum), as well as the yellow flowers obtained from another Indian 

 cotton (G. neglectum) contained isoquercitrin and gossypitrin. Usually 

 quercetin and gossypetin could be found in the extracts as products of 

 hydrolysis of these glucosids. No gossypitrin could be found in the red 



' This paper is the first of a series on the chemistry of the cotton plant. 

 ' This •work was done in cooperation with the Bureau of Entomology. 

 ' Reference is made by number (italic) to " Literature cited," pp. 35i~352- 

 * Perkins gives " rossrum," an evident typographic error for " roseum." 



Journal of Agricultural Research, Vol. XIII, No. 7 



Washington, D. C. May 13, 1918 



ni (34s) Key No. E-8 



