THE SPONGES OF THE WEST-CENTRAL PACIFIC 



283 



fallen, rotting fruit, an almost unbelievably immense population of flies had 

 bred. In its lee the shallow water was very richly supplied with sponges, 

 especially Hippiospongia communis of the best commercial quality that I 

 found anywhere in the Micronesian region. There were also Dysidea herb- 

 acea, Echinoclathria waldoschmitti, Axinosia xutha, Stylotella agminata, Lip- 

 astrotethya ana, and Leucetta avocada. Of these, I found only the Hippio- 

 spongia and Stylotella also in Truk. 



Dysidea herbacea occurred also in the Marshalls (Ailing-lap-lap) and 

 has been hitherto recorded from the region of the Indian Ocean, East Indies, 

 and Australia. I found Leucetta avocada also in the Palaus ; it is not recorded 

 elsewhere. 



On Ponape, I studied the lagoons, especially in regard to sponges, at 

 the southwest portion, northwest portion, and mid-eastern portion of the 

 island. It was possible here, as not at Truk or the Palaus, to survey a line 

 all the way from shore across the lagoon to the outer reef. The greatest 

 sponge abundance was found definitely to be in the deeper water halfway 

 between reef and shore. Nearer the shore the abundance decreased only 

 slightly. Near the outer reef it fell off sharply. From the line of breaking surf 

 toward the outer shore as far as the reef might be uncovered or nearly un- 

 covered at low tide, I could find no sponges at all. For a hundred meters or 

 thereabouts just inside the reef, sponges were extremely rare, and those 

 that did occur were usually Stylotella agminata or some of the incrusting ones 

 that live under stones. In view of these observations at Ponape, I do not 



Text Figure No. 193, 

 Map number 8. Ponape. 

 The scale reads in kilo- 

 meters. Stars show areas 

 where sponges were most 

 studied. 



