THE SPONGES OF THE WEST-CENTRAL PACIFIC 



89 



This species is unique within the genus Callyspongia for its sand-filled 

 fibers. The species name is obviously derived from the Greek word for 

 sand-bearing. 



FAMILY DESMACIDONIDAE, Gray 



GENUS GELLIODES Ridley 



Gelliodes gracilis Hentschel 



Text Figure No. S3 

 Plate V, Figure b 



This species is here represented by the following: 

 U.S.N.M. No. 23125, My No. M. 507, collected September 2, 1949, by diver 

 northwest of Koror in the Palau Islands near Ngarebagal Island. The 

 depth was 3 meters and the substrate was dead coral. 



The species was quite common throughout most of the Palau Archi- 

 pelago, as observed. 



The shape is ramose and the branches end in very small prolongations, 

 which may be incipient additional branches. The vertical measurement 

 reached at least 14 cm, and the branches in transverse section are about 

 1 by 2 cm. 



The ectosome and endosome color in life was a vivid lavender. The 

 consistency was spongy but easily torn. 



The surface is comparatively smooth, or punctiform, as a result of the 

 very conspicuous pore areas. The latter are each about 1 mm in diameter 

 and approximately 3 mm apart, center to center. Each contains a dozen or 

 so actual pores, about 50 ll to 125 /a in diameter and 100 /x to 175 ll apart, 

 center to center. The oscules are from 1 to 2 mm in diameter and 1 to 2 cm 

 apart, occurring chiefly on the lateral surfaces of the branches, not apical or 

 terminal. 



The ectosome is not conspicuous, but with a microscope it is possible to 

 discover an extremely thin dermis, about 4 /x thick, which occurs as a ceiling 

 to small ramifying subdermal cavities. This ectosome contains no spicules 

 or other skeletal structures. The endosome is a neat fibro-reticulation. 



B^ 



Text Figure No. 53. Sp 



icules of Gelliodes gracilis, X 781. A: Oxea. B: Larger sigmas. 

 C: Smaller sigmas. 



