224 the president's address. 



vermicularis live in the digestive cavities of holothurians. Fish 

 live in sea-anemones, and Oxybeles lumbricoides lives in a star-fish; 

 the young of Caranx trachurus frequent the cavities of the medusa 

 Chrysaora isocela, and there are plenty of other instances of asso- 

 ciation between fish and medusse. Some authors might call this 

 parasitism, and some might not, but of one thing we may be certain, 

 viz., that like all the other creatures which I have mentioned to- 

 night, whether they be called parasites, messmates, mutualists, or 

 anything else, they are not less wonderful nor less interesting than 

 other forms of organic life, and that the study of them will amply 

 repay everyone who has the time to devote to that pursuit, and 

 the inclination so to devote it. 



