Zoology. — ''Experimental Budding in Fimgin fungites" . My Dr. 

 H. BoscHMA. (Communicated by Prof. C. Ph. Sluiteh). 



(Communicated at the meeting of January 27, 1923). 



A large number of the Fungiae to be found on coral reefs display 

 anomalies mostly arising from the destniclion of part of the living- 

 tissue. In many cases the destroyed stretches of living tissue are 

 attacked by small algae, which penetrate to a considerable depth, 

 and gradually spread into the living tissue. Such decaying spots of- 

 ten stimulate the adjacent tissue, wiiich consequently exhibits a more 

 energetic growtii-activity than usual. The result then is that some- 

 thing like a raised rim arises on the border between the living and 

 the defunct part. In many cases this greater activity is also mani- 

 fested even in the formation of buds. In a previous publication I 

 discussed this budding in adult Kungiae '). Here I also pointed to 

 the fact that algae-parasitism is one of tlie chief causes of budding 

 in adult corals. Generally the destruction of only a small part of 

 tiie living tissue sutfices for tiie vicinity to be stimulated to a more 

 energetic grow I h-aci i v i ty . 



This induced me to endeavour to develop buds experimentally in 

 Fungia ftmgites. My material for this experiment consisted of spe- 

 cimens of Fungia fang itex from the reef of the island of Edam neai- 

 Batavia. The most normal corals devoid of luids or other anomalies 

 were selected. To destroy part of tlie tissue a small piece of putty 

 was pressed into the central region of the oral suiface of some fifty 

 specimens on the 18"> and the 19"' of August 1921. The putty 

 was held fast on either side of the mouth by the septa. The corals 

 were then restored to their original places. 



In this experiment, I expected the destruction of part of the central 

 tissue to extend to the mouth in most of the specimens, as this 

 would most likely bring about a strong reaction to the lesion, so 

 that budding would soon ensue. True, the ingest of food would 

 hereby be slightly impeded. But considering that Fungia feeds only 

 partly on organisms other than zooxanthellae, and considering moreover 



') H. BoscHMA, "On Budding and Coalesceucfi of Buds in Fungia fungites and 

 Fungia actiniformis." Proceedings Kon. Ak. van Wetensch. Amsterdam. Vol. XXIV, 

 1922. 



