394 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



In the male 48% greater than CV of chord. 



In the female 8% " " " 



In both sexes taken together 14% " " " 



Comparing the Average Deviations of the two dimensions, we find a still 

 greater proportional difference. 



•o 







»0 



.28 ...2? ...30 ...3/ -32 -33 ...io -lOi -11 ...11.5 ...12 ...12.5 

 LENGTH BREADTH 



Figure 2. 



Figure 3. 





.13.4 .J3.1 ...m ...m JSM JS.1 ...M 



CHORD 



Figure 4. 



,1b ...17 ...18 ...? ...20 

 MARGIN 



Figure 5. 



Diagrams illustrating Individual Variation in Tityreus abbotii. 



Numbers of specimens plotted as ordiiiates ; measurements (in millimetres) as 

 abscissa?. Tlie numbers appended to the ordiuates indicate tlie maximum 

 measurements in the respective groups. 



— — — Both Sexes ; Males; Females. 



