LIST AND CONTENTS OF BULLETINS 1 TO 100. 35 



vigor; tlio relation of hvbridity to diseast- resistance ; iini)rovenu'nt by selec- 

 tion; are earlv or late "varieties tlie more resistant.'; relation of soiiree of 

 seed and enltuVal methods to disease resistance; eoniposition and eliaraeter 

 of tnbers as related to rot resistance; character of stem and foliaj^e as 

 related to disease resistance — Disease-resistant varieties of Europe: (ireat 

 Britain ; Germany and Holland ; France and Belg-inm— Disease-resistant varie- 

 ties of America: "lnvesti<iations at the experiment stations; work at the Ver- 

 mont station ; information secured by a circular of inquiry : resistance to 

 scab — Summary. 



No. 88. AVeevil-Resistinfr Adaptations of the Cotton Plant. "By O. 



F. Cook, Biononiist in Charge of Investigations in the 



Agricnhural Economy of Tropical and Snhtroincal 



Plants. 15)0(). 87 pp., 10 pis. Price. 10 cents. 



Contents : Introduction — Selective influence of the boll weevil — (leneral pro- 

 tective characters: Dwarf habit and determinate <>rowth of Kekchi cotton; 

 variations in the Kekchi cotton; ettects of Cuatemalan conditions on United 

 States varieties; acclimatization of Kekchi cotton in the United States; early 

 bearing facilitated by long basal branches; early rejection of superfluous 

 squares; seasonal bearing of perennial varieties; annual cutting back of 

 perennial varieties; hairy stalks and leaf stems; pendent bolls — Extrafloral 

 nectaries: Xectaries of tlie leaves; exteriuil nectaries of the involucre; inner 

 nectaries of the involucre ; nectaries of (iuatemalan Sea Island cotton ; continued 

 secretion of nectar; bractlets subtending inner nectaries; efficiency of the 

 kelep jH-oteetion; other nectar-bearing ])lants visited by the kele])s — The invo- 

 lucre as a i)rotective structure: Involuernl bracts grown together: ap])ressed 

 margins of bracts; large involucres of Kekchi cotton; opening, or Haring, of 

 bracts. avoided ; hairj- margins of involiicral bracts; extent of protection by 

 involucre; advantage of open involucres — Behavior of parasitized buds: 

 Shedding of weevil-infested squares; countings of flared and fallen scpiares ; 

 ])roliferati<)n of internal tissues of buds; causes and conditions of bud ])ro- 

 liferation ; proliferation in other varieties — Protection of the bolls: Persist- 

 ence of flowers ; immunity of very yoinig bolls ; rapid growth of young bolls ; 

 thick-walled bolls; toughlinings of chambers of bolls; proliferation from the 

 wall of the boll ; time required for proliferation ; efficiency of adaptive charac- 

 ters of bolls; bacterial diseases following weevil injuries; breeding in buds a 

 derived habit ; relation between proliferation in buds and in bolls — Protecti(m 

 of seeds by lint: Protective seed arrangement in Kidney cotton — Cultural value 

 of Kidney cotton — The nature and causes of adaptations — Conscious and uncon- 

 scious selection — Summary of adaptations: Classification of adajjtations ; 

 adaptive characters of different types of cotton — Concluding remarks — Descrip- 

 tion of plates — Index. 



No. 89. Wild Medicinal Plants of the United States. By Alice 



Henkel, Assistant, Drug-Plant Investigations. 1900. 70 



pp. Price, 5 cents. 



Contents : Catalogue of common and scientific names of wild medicinal 

 plants, with descriptions, statements as to geographical distribution, .parts 

 used, etc. 



No. 90. Miscellaneous Papers. * I. The Storage and Germination 

 of Wild Rice Seed. By J. W. T. Duvel, Assistant. II. 

 The Crown-Gall and Hairy-Root Diseases of the Apple 

 Tree. By George G. Hedgcock, Assistant. * III. Pep- 

 permint. By Alice Henkel, Assistant. IV. The Poison- 

 ous Action of Johnson Grass. By A. C. Crawford, Phar- 

 macologist. 1900. 34 pp., 5 pis., 3 figs. Price, 5 cents. 



Contents : The storage and germination of wild rice seed : Introduction — 

 Distribution — Habitat — Germination of the seed — Fall seeding versus spring 



101 



