1S2 



THE AMEBIC AN NATURALIST [Vol. LIV 



THE INTENSITY OF ASSORTIVE PAIRING IN CHRO- 

 MODORIS 1 



The pairing of the hermaphroditic nudibranch Ckromodoris 

 zebra is accomplished in such a manner that there occurs a con- 

 siderable degree of assortive conjugation with respect to size. A 

 report 2 presenting evidence in support of this conclusion was 

 based upon the examination of Chmmoilnns population in Great 

 Sound, Bermuda, at a season when a considerable percentage of 



cm 



the individuals exhibited injuries of the dorsal region of the 

 mantle. These injuries, resulting in a distortion of the dorsal 

 part of the body, made it necessary in estimating size to measure 

 the total length of the animals — from anterior edge of the buccal 

 veil to posterior termination of the foot. For practical purposes 



