298 



E. C. FAUST. 



factory and used in all the following measurements. For all 

 these data each measurement was recorded in sequence and later 

 incorporated into a polygon plot. All crooked or curved indi- 

 viduals were entered separately and not used except as a check. 



Frequency. 



Length in n. 22.68 23.76 24.84 25.92 27.00 28.08 29.16 30.24 31.32 32.40 33.48 34-56 35.64 



FIG. ii. Bimodal curve of variability of chromatic-rod length for 4r. Greater 

 number of spermatozoa grouped around the upper mode, M". 



Frequency. 



Length in M.. 22.68 23.76 24.84 25.92 27.00 28.08 29.16 30.24 31.32 32.40 33.48 34-56 35-64 



FIG. 12. Bimodal curve of variability of chromatic-rod length for 4!. Greater 

 number of spermatozoa grouped around the upper mode, M". 



