44 THE SPONGES OF THE WEST-CENTRAL PACIFIC 



Dendrilla. No separate oscules could be made out, however, and probably 

 some of the small openings are inhalant as well as exhalant. 



The ectosome is a thin fleshy dermis, and the endosome is also quite 

 fleshy. The flagellate chambers are sack-shaped or eurypyllous but rather 

 small, only about 40 jx in diameter. 



The skeleton is chiefly dendritic, but there are definitely a few connections 

 between fibers, making somewhat of a network ; in fact, some meshes are only 

 300 [j. in diameter. The fibers are larger near the base of the sponge, and be- 

 come smaller as they branch often and reach nearer the surface. They de- 

 crease from about 180 /a down to 50 \x or smaller. They are made of pale 

 yellow-gray translucent spongin, and in many places, particularly in the larger 

 fibers, they are cored with foreign material. This foreign material often repre- 

 sents only about the central third of the fiber. 



This species is sharply characterized by its distinctive color. The species 

 rosea from the West Indies is rose-red; the common Australian species 

 semicanalis and arenifibrosa are dull brown; and the type species (lactea) 

 from the Red Sea is milky white. The other species also have distinctive 

 characteristics which separate them from phlogera. For example, semicanalis 

 has erect, hollow cylinders leading to its oscules, and repens from Chile has a 

 peculiar warty structure. 



The name selected is derived from a Greek word meaning "flaming." 



GENUS DENDRILLA Lendenfeld 

 Dendrilla nigra (Dendy) de Laubenfels 



Text Figure No. 24 



This species is represented by the following : 

 U.S.N.M. No. 22873, My No. M. 169, collected on July 13, 1949, by diver 



at Likiep Atoll in the south side of the lagoon near Eotli Islet. The 



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

 U.S.N.M. No. 23111, My No. M. 493, collected on September 1, 1949, by 



divers in Iwayama Bay, Koror, in the Palaus. The depth was 2 meters 



and the substrate was dead coral. 



The Likiep specimen was incrusting, probably because it was a young 

 specimen or one not thriving. The specimen from Iwayama Bay was more 

 lamellate and irregular in shape. The color of the sponge, both inside and 

 out, was inky blue-black. The consistency was softly spongy, easily torn. 



The surface is covered by irregular conules, about 1 mm high and 2 to 

 5 mm apart, but considerable areas of the surface may be smooth. On the 

 other hand, they are not shiny or glistening smooth. The pores are about 

 40 fi in diameter and very abundant, in places only 60 /x apart, center to 

 center. The oscules vary greatly with the size of the sponge, being indis- 

 tinguishable in the young specimens mentioned above, but up to 6 mm in 



