AGRICULTURAL EXPERIMENT STATION OF THE 
RHODE ISLAND STATE COLLEGE. 
BULLETIN 162, APRIL, 1915. 
SEX RATIOS IN PIGEONS, TOGETHER WITH 
OBSERVATIONS ON THE LAYING, INCUBA¬ 
TION AND HATCHING OF THE EGGS.* 
BY LEON J. COLE AND WILLIAM F. KIRKPATRICK. 
Introduction. 
The results presented in the present paper have been obtained 
in the course of studies on inheritance in pigeons, two reports on 
vdiich have already appeared (Cole, 1914; Lloyd-Jones, 1915). As 
in the first of these, the data in the present instance have resulted 
from experiments begun at the Rhode Island Agricultural Experiment 
Station in 1907, and continued by the senior author at the Wisconsin 
Experiment Station since the summer of 1910. It is only fair to 
state that the junior authorf had practically full charge of keeping 
the field notes and taking records up to July, 1910, though the senior 
author made practically all the descriptions and determinations of sex. 
All sex determinations are based on the performance of birds which 
have actually bred, or on dissections. In no case has sex been 
recorded from the behavior of young birds, unless so verified later. 
♦Contribution 215 from the Agricultural Experiment Station of the Rhode Island State College. 
Papers from the Department of Experimental Breeding of the Wisconsin Agricultural Experiment 
Station, No. 5. 
fNow Professor of Poultry Husbandry, Connecticut Agricultural College, Storrs, Conn. 
