294 GILBERT C. BOURNE. 



with an example of the nurse-stock.^ In this I was very much 

 disappointed, for Professor Moseley succeeded in finding a 

 specimen at Tahiti in the course of a few hours' search, whilst 

 I was unsuccessful day after day. Although the Fungise at 

 Tahiti lay in only three inches of water, and the search was 

 an easy one, he mentions the great difficulty he had in finding 

 the nurse-mass among the numerous adult forms on the reef; 

 and in my case, where they lay in three feet or more of water, 

 it is possible that I may have overlooked the small nurse-stock 

 and the smaller recently detached Fungiae ; this is the more 

 likely since both the nurse-stocks and the young forms would 

 probably remain hidden beneath the great flat plates of dead 

 Madrepore which form the basis of the mounds of living coral. 

 Yet I can scarcely believe this to be the case, for not only did 

 I search very closely by wading and diving among the corals, 

 but I frequently turned over the above-mentioned flat plates 

 of coral-rock and examined their under surfaces without ever 

 finding a single example, nor did I ever meet with a group of 

 very small forms, nor with anything like the group of nurse- 

 stocks attached to the corallum of an old and dead Fungia, as 

 figured by Stutchbury (39). I am inclined to believe that 

 sexual reproduction followed by asexual reproduction by 

 budding from a nurse-stock takes place in Fungia only 

 at certain seasons of the year, and that it was not in 

 progress during ray stay at Diego Garcia. This seems the 

 more probable because I have found no trace either of ova or 

 of spermatozoa in any of the large specimens which I have 

 brought home for examination. Reproduction in Fungia 

 appears to be effected also by budding and by simple fission. 

 In the British Museum there are several examples of the 

 former process, in which indubitable buds can be seen growing 

 from the base of a large Fungia. The buds always arise from 



' Semper (38) calls the nurse-stock of Fungia a Strobila, but as this 

 name was originally applied to the dividing parent-stock of Aurelia, which is 

 essentially diiferent from the bud-producing parent-stock of Fungia, and since 

 it is objectionable to use the same name for two very different phenomena, I 

 use the word nurse-stock for the fixed parent of Fungia. 



