260 



THE SPONGES OF THE WEST-CENTRAL PACIFIC 



or similar tetraxons, with a fourth very small ray projecting into the lumen 

 of the cloaca. 



Tanita comments that this is "remarkable for the presence of well- 

 developed sub-gastral triradiates and of large tubar triradiates." This was 

 described by Tanita, 1943, page 454, as Lcucandra palaoensis. 



FAMILY SCYPHIDAE de Laubenfels 



GENUS SCYPHA Gray 

 Scypha plumosa (Tanita) de Laubenfels 



Text Figure No. 183 



This species is not represented by any specimen in the present collection 

 but was found in the Palau Archipelago. There is no data as to the ecological 

 or geographical placement. Some specimens were collected by Mr. Hiro and 

 some by Dr. Abe, as quoted by Tanita. 



This is a tubular sponge, ranging up to 3 cm and 2 cm in diameter. 



The color is described as being white, and the consistency as fragile. 



The surface is strongly hispid. The pores are not described, and the 

 oscules range up to 5 mm in diameter. There is one such oscule or upper 

 opening of cloaca to each individual. 



There is only a thin dermal structure, and the endosome exhibits typical 

 sycon architecture. 



The skeleton of this species includes three types of oxeas. A common 

 kind, perpendicular to the surface, is about 32 /x by 2400 /x. Amazingly 

 there are others, also hispidating the surface, only 3 x<, thick by about 4800 /x 

 long. Around the cloacal opening there are coronal oxeas, 8 /x by 2400 ti. The 

 dermal triaxons have rays which are about 16 /x by 200 /x. They are sagittal, 

 with the clads tangent to the surface, and the rhabds protruding. The triaxons 

 of the chamber layer are also sagittal, their rays being about 18 xi by 300 /x. 

 The clads are nearer the cloaca, rhabds point toward the exterior. Other 



Text Figure No. 183. Spicules of Scypha plumosa, X 90, after Tanita. A: Tylostyle, 

 from distal end of flagellate chambers. B: Tubar triact from distal end of flagellate 

 chambers. C: Tetract from oscular margin. D: Subcloacal triact. E: Cloacal tetract. 



