180 ON A CASE OF COMMENSALISM. 



NOTE XXIV. 

 ON A CASE OP COMMENSALISM 



of a Fish (Amphiprion intermedius Schleg.) and a large 

 Sea-Anemone (Discosoma-spec.) 



Dr. R. HORST. 



Among an interesting collection of Invertebrate animals 

 from Sabang-bay (Poeloe Weh) brought together by Mr. G. 

 A. J. van der Sande, Surgeon in the Dutch naval service, and 

 presented by him to the Leyden Museum, there is a large 

 Anemone, belonging to the genus Discosoma. About this 

 specimen Mr. van der Sande writes: »in loosening the 

 Anemone from the coral, upon which it was fixed, suddenly 

 some small fishes came in sight and made an attack on the 

 hands of the hospital-waiter who assisted me and on those 

 of my self. Involuntary we were frightened and retracted our 

 hands, and as the trouble of the water ceased, we saw 

 small white-and-brown banded fishes hovering above the 

 Anemone, which every now and then retired between the 

 tentacula and made a renewed attack as soon as we again 

 tried to release the Anemone from the coral". According 

 to Miss Dr. C. Popta, who examined the fishes, they proved 

 to be young individuals of Amphiprion intermedius Schleg. 



It is not the first time that such a relation is stated 

 between Anemones and fishes; more than thirty years ago 

 Dr. C. Oollingwood already made a similar observation 



Notes from the Leyden ]Miiseuin, Vol. XXIII. 



