STATISTICAL STUDIES OF FLOWER NUMBER 
PER HEAD IN CICHORIUM INTYBUS: KINDS 
OF VARIABILITY, HEREDITY, AND 
EFFECTS OF SELECTION 
By A. B. Stout AND HELENE M. Boas 
The New York Botanical Garden 
(WITH PLATES 10—13) 
TABLE OF CONTENTS 
PRP CIES EOE OO aS e ue Г Te а лур ки. КЫШЛЫК aoa ста 335 
EVIEW OF LITERATURE PERTAINING TO NUMBER OF FLOWERS PER HEAD IN 
dad дни а QU GER EC Qu IE dA xar CE C Ro 337 
с udwig's evidence that flower-number is a specific character...... 337 
II. Theories regarding the evolution and development of flower sie thes 
рег нен” осу ы ee ea IQ UNT NE eredi y) S esie моно 339 
III. Special criticisms of facts and theories. ........... essen 342 
IV. Evidence of intraseasonal уагіаЫ су........................... 344 
V. Observations and experiments on the influence of environment. 345 
VI. Studies of иаша ықш Je Cis а аты Аы UR ТАР Еа) 347 
VII. Evidence that position is a factor in partial variability. .......... 348 
VIII. Special views dris heredity, differentiation, ae symmetry, 
Пе Е by Pearson and by Bateson. з o oui. Aor yn 51 
IX; Evidence of hereditary variation у оаа Виа кке 354 
X. Previous study of flower number in Cichorium Inlybus........... 356 
UIA аы чс ao на ул е LLLI ЫЗ Qu C e E TR аны 356 
THE PROBLEMS IN CIOHORIUM INIYBUS еа (OR x eee tren 357 
MATERIAE ЖҰП METHODS. OU Di cs ИЛЛ УУ TTL nde sc di а as E ORE 358 
PRESENTATION OF DATA FOR FLOWER NUMBER IN СНІСОВҮ................. 362 
General survey of the kinds of variability present. ................ 362 
x. Pura variable V. Oe es hs УУ PARA T E xad reist mr 362 
A краят дана РА p UV ИА ue EU IU MN ul. атар 362 
JA ТИРА ОЕ ИЕ ааа vaa s PN EET IS 366 
. Indiv: iul enitn On оК ҚАС ge ah eg E аот н 379 
Il. denies Weatment Of dala опори ee аа 215. 380 
III. Detailed presentation of data bearing on 
1. Relation of rem h of ае MR to tate of change. ........ 85 
2. Significance of the range of variability in flower number per head. 391 
3. 27 of flower don din per head to position of heads. ........ 
ive studies regarding розШоп..................... 393 
