The Anatomy of the Madreporarian Coral 

 Fungia. 



By 



Gilbert C. Bourne, B.A., F.U.S., 



New College, Oxford. 



With Plates XXIII, XXIV and XXV. 



During a visit, extending from the middle of September, 

 1885, to the middle of January, 1886, to the island of Diego 

 Garcia, an atoll lying in S. lat. 7° 13', E. long. 72° 23', I 

 was able to collect and preserve a large number of specimens 

 of Fungia dentata, which form the subject of the present 

 memoir. 



The Fungiae were very abundant within the lagoon, espe- 

 cially among the knolls and banks of growing coral on its east 

 side, where, at low spring tides, they could be collected by 

 scores from depths ranging from three to ten feet. They 

 occur singly, more usually in groups of five or six, among the 

 massive Astraeids and Madrepores of which the knolls are 

 chiefly composed, usually lying in a hollow or basin, or half 

 hidden beneath the spreading branches of some large Madre- 

 pora, and are thus protected from being swept away by the 

 tides which set strongly across the knolls. 



Specimens of a diameter of three inches and more were 

 extremely common, but it was very rarely that I could find 

 any of smaller size ; the smallest that I was able to procure 

 measures as much as "two inches across, and a prolonged 

 search failed to reward me with a single smaller specimen, or 



VOL. XXVII, PART 3. NEW SER. Y 



