THE SPONGES OF THE WEST-CENTRAL PACIFIC 



Text Figure No. 2. Fibers of Spongia zimocca, X 182. A bit of tbe abundant network is 

 shown in the foreground; a portion of one of the rare primary or cored fibers in the 



background. 



The ectosome is a thin dermis about 12 t<, thick and may be removed 

 with moderate ease. It comes loose spontaneously on macerating specimens. 



The endosome is a typical Spongia-type, crowded with conspicuous flag- 

 ellate chambers about 25 jx in diameter. It is, of course, permeated by a dense 

 fibro-reticulation. 



The skeleton comprises moderately numerous ascending or principal 

 fibers, about 80 [x in diameter, crowded with foreign debris. The much more 

 common fibers, which may perhaps be called secondary, are about 20 it in 

 diameter and form polygonal meshes about 100 /x across. They are very 

 irregular in size. 



The species Spongia zimocca was established by Schmidt 1862, page 23, 

 from the Mediterranean. It also has been recorded as from the Australian 

 and West Indian regions. Commercially, it is commonly referred to as the 

 "yellow" sponge, because the macerated fibers exhibit a somewhat golden 

 yellow or almost orange color. Lendenfeld in 1885, page 485, established 

 a species which he called Euspongia irregularis. This is obviously very 

 closely related to Spongia zimocca and differs only in that the fibers of 

 irregularis are somewhat irregular in diameter from one place to another 

 throughout the length thereof. Therefore, de Laubenfels 1948, page 14, 

 reduced it to a subspecies of Spongia zimocca. Sponges of this subspecies 

 appear to be especially common in the vicinity of Australia, and the range 

 also extends into the Indian Ocean and East Indian regions. An important 



