158 THE SPONGES OF THE WEST-CENTRAL PACIFIC 



No sharp distinction can be made between ectosome and endosome in 

 exceedingly thin sponges. The spicules are arranged partly in confusion, 

 and in other cases with the points upward perpendicular to the surface. 



The skeleton consists of both megascleres and microscleres. The former 

 are all tylostyles, but of two size ranges. The larger, which is usually 

 somewhat less common than the smaller, may reach a dimension of 9 p by 

 435 p. Spicules of the smaller, more abundant category range from 2 p to 

 3 p in thickness and 200 fx to 400 \x in length. In the abnormally thick speci- 

 men mentioned above (M. 205), the spicules were extra small, only 1.5 p by 

 180 [x. The microscleres and other aspects of this specimen were quite typi- 

 cal. The microscleres include toxas of two size ranges. The larger size are 

 from 55 fx to 80 p long, and the smaller from 15 p to 33 p long. In those 

 specimens in which one category is a little larger than average, the other 

 category is also a little larger than average, and vice versa. Among the 

 microscleres there are also palmate isochelas ranging from 12 p to 20 p in 

 length but usually between 15 p and 17 p. Those of this type, from the 

 Ailing-lap-lap specimen (M. 106) were strongly contort, so twisted in fact 

 that if one of the shovels was in face view, the other could be seen only in 

 profile. This might be considered so distinctive that a separate species should 

 be erected for the Ailing-lap-lap sponge, but de Laubenfels (1947, page 35), 

 in making an ecological study of sponges in the vicinity of Beaufort, North 

 Carolina, reports extensively on Microciona prolifera, which exists there 

 in abundance. Careful study showed that specimens undoubtedly of the 

 same species (in among others that were typical) had this palmate isochela 

 with the contort structure. In fact, in one portion of the same sponge chelas 

 might be normal, while in another portion they were twisted. 



This new species is distinctive for its lack of plain styles, having only 

 tylostyles, and for the two categories of toxas which are also worthy of 

 comment. 



The specific name alludes to the beauty of this species. 



GENUS FASUBERA de Laubenfels 

 Fasubera debrumi, new 



Text Figure No. 103 



This species is here represented by the following : 

 U.S.N.M. No. 22869, My No. M. 164, here designated as type, collected 

 July 11, 1949, by diver at Likiep Atoll from the east end of the lagoon 

 near Lado Isle. The depth was 5 meters, and the substrate was dead 

 coral. 



This species is a thin incrustation less than 1 mm thick, and the lateral 

 dimensions are at least 15 cm. 



The color in life was blood red, and the consistency was fleshy. 



