452 PROCEEDINGS OF THE NATIONAL MUSEUM vol.83 



endosome. They are of two sorts, tylasters about lO/x in total diam- 

 eter, and oxysplierasters only about 7/i in diameter. 



This species was first described by Schmidt (1870, p. 52) from the 

 West Indies and has since been recorded from the west coast of 

 Mexico, the east coast of South America, both east and west coasts 

 of Africa, the Indian Ocean, East Indies, and New Zealand. The 

 Panamanian specimens are quite typical of the race as found around 

 the world. 



TABOGA, new genus 



Diagnosis. — Family Tethyidae. The radiate, corticate structure 

 resembles Tethya, but with very pronounced development of root 

 structures. The strongyle-oxeote megascleres also resemble those of 

 Tethya. The microscleres include spherasters somewhat like those 

 of Tethya, but in addition there are typically three other distinct 

 categories of asters, one of wliich is peculiar for sharply branched 

 terminations to its rays. 



Genotype. — Taboga taboga, new species. 



TABOGA TABOGA, new species 



Figure 43 



Holotype.— U.S. 'N.M. no. 22216. 



This species is moderately abundant intertidally on Taboga Island 

 at the Pacific end of the entrance to the Panama Canal; it was not 

 found elsewhere. The shape is subspherical, up to slightly over 2 cm 

 in diameter, but most of the specimens are only about 1 cm in diam- 

 eter. Each is attached to the substratum by ribbon-shaped roots, 

 only 0.1 to 0.2 mm thick but usually 2 mm wide. There are ordinarily 

 5 to 15 such roots extending from each sponge and reaching out in 

 some cases as much as 1 cm or more, anchoring the mass very firmly 

 so that it may be held in place in spite of vigorous wave action. In 

 life the surface is covered with a dull red layer 1 mm deep. This 

 consists of a spicule plush of megascleres standing erect, rarely 

 embedded in the white surface below them, and interspersed with 

 rather loosely placed reddish cells that may or may not be proper to 

 the sponge. The regularity with which they occur and the uniformity 

 of their color suggest, however, that they are proper. 



Below this red layer is a white layer of equal thickness. Its struc- 

 ture is corticate to cartilaginous. It represents the most extreme 

 development of contractile tissue in any sponge known to me. Below 

 the red-and-wliite layers the endosome is ochre-j^ellow and permeated 

 by transparent fascicular columns packed with spicules radiating 

 from the central point of the sponge to the surface. Above them the 

 surface is thrown into tuberculous protrusions not quite 1 mm in 



