132 THE SPONGES OF THE WEST-CENTRAL PACIFIC 



GENUS LISSODENDORYX Topsent 

 Lissodendoryx oxytes, new- 

 Text Figure No. 83 



This species is here represented by the following : 

 U.S.N.M. No. 22929, My No. M. 235, designated as type, collected Septem- 

 ber 2, 1949, by divers northwest of Koror in Komebail lagoon in the 

 Palaus. The depth was 5 meters, and the substrate was dead coral. 



Some bits of this species may be described as incrusting, and at such 

 places it is less than 1 mm thick. The most characteristic matter in regard 

 to its shape is its tendency to penetrate. The coral, where oxytes was found, 

 was ramified by galleries which appeared to have been made by the sponge 

 Cliona. Such is probably the case, because a few of these galleries did con- 

 tain both spicules or actual fragments of living Cliona, However, the ma- 

 jority of these galleries, which were 1 to 2 mm in diameter and were ramify- 

 ing through the calcareous material, were filled not with Cliona but with the 

 species now under discussion. It is positively not suggested that the Lisso- 

 dendoryx excavated these cavities ; it merely penetrated them. Whether the 

 Cliona died and left them first empty or whether the Lissodendoryx actually 

 drove out the Cliona could not be ascertained. Annandale, 1915, pages 457 to 

 478, describes about a dozen other species of sponge which similarly invade 

 the burrows of Cliona. 



The color in life was extremely dark purple, but immediately upon 

 placement in alcohol it changed to a flesh color. This color change is un- 

 expected and quite novel. The consistency was slimy, softly colloidal. 



The surface is shiny smooth, with no pores or oscules visible to the 

 naked eye. They cannot be found in preserved specimens. The pores un- 

 doubtedly are closed. 



There is little protoplasmic differentiation for ectosome, but special ecto- 

 somal-type spicules occur and may indicate the theoretical presence of such 

 structure. The sponge is chiefly endosome, as might be expected from its 

 occurrence in excavations. 



C= 



3-. 



^ ==o 



g=^c C^v 



Text Figure No. 83. Spicules of Lissodendoryx oxytes, X 781. A: Ectosomal tylote. The 

 entire spicule is shown, but in two parts. B: Endosomal acanthostyle. C: Arcuate 



isochela. D: Sigma. 



