48 THE SPONGES OF THE WEST-CENTRAL PACIFIC 



The skeleton consists of translucent, pale yellow fibers with concentric 

 layers of spongin, and no cores. They are completely dendritic, branching 

 often, but seldom or never anastomosing. They arise from a basal plate of 

 spongin and, at first are about 150 /x in diameter; but, as they approach the 

 surface, they become smaller and smaller, due to the branching — finally 

 becoming about 25 [x in diameter. 



These specimens here discussed do not differ in any noticeable respect 

 from those of Aplysilla sulfurea, except that each of them is so small and 

 undeveloped. One wonders whether they might possibly display differences 

 from sulfurea if they were to grow in more luxuriant form. 



Aplysilla sulfurea was first described by Schulze 1878, page 405, from 

 the Mediterranean. It has been reported from the Atlantic Coast of North 

 America by de Laubenfels, 1947, page 35, and from Australia by Lendenfeld, 

 1889, page 707. 



Aplysilla polyraphis de Laubenfels 



Text Figure No. 27 



This species is here represented by the following: 

 U.S.N.M. No. 22883, My No. M. 182, collected August 1, 1949, by diver in 

 eastern Ponape (Matalanim) from a reef in the lagoon near an entrance 

 into the lagoon. The depth was 5 meters, and the substrate was dead 

 coral. 



This species is incrusting and, as found, had several patches, each less 

 than 1 mm thick and covering about 100 square cm. 



The endosome and ectosome color in life was purple ; and, upon handling, 

 it exuded large quantities of crimson or royal purple colloid. The consistency 

 was dual : the conules were definitely spongy, but the ground stuff between 

 them was fleshy. 



Text Figure No. 27. Portion of the fiber of Aplysilla polyraphis, X 182. 



