THE SPONGES OF THE WEST-CENTRAL PACIFIC 227 



lagoon near the shore. The depth was 3 meters, and the substrate was 

 dead coral. This species was common throughout Ponape, especially 

 southwest Ponape in the province of Kiti. 



The shape of this sponge is basically massive, with digits rising up to as 

 much as 8 cm high. The basal mass is often as much as 13 cm and the digits 

 2 to 3 cm in diameter. 



The color in life was bright fiery orange, and this color has been main- 

 tained moderately well in alcohol. The endosome had the same color as the 

 ectosome. The consistency was spongy, but easily torn. 



The surface is between tuberculate and conulose, with one eminence for 

 each square mm. These tubercles are about 500 p. high. The pores are about 

 40 p. to 60 p in diameter and about 80 p. apart. The oscules are very muscular 

 and close at the time of collection, but there is evidence of a diameter of about 

 7 mm in life. There is one oscule at the summit of each of the digitate pro- 

 jections. 



The ectosome comprises a definite dermis, 30 p, thick. The endosome 

 contains tracts, 100 p to 200 /x in diameter, ascending almost perpendicularly 

 to the surface. These are essentially protoplasmic and also contain numerous 

 spicules but apparently not any spongin. These tracts are about 400 p. apart 

 and in many cases (but not always) are the cause of the surface conules or 

 tubercles as already discussed. There are vague connective fibers or tracts, 

 which are about 20 p. to 60 /x in diameter. 



The skeleton comprises oxeas which are usually about 4 [x by 150 \x but 

 in some cases up to as much as 10 p. by 610 p,. There are also immense 

 numbers of astose spicules. There are small asters 7 p. to 8 p in diameter, 

 which are chiasters or t}dasters with microspined rays. Then there are oxyeu- 

 asters with fewer rays (often only five) but these rays are microspined and 

 the total diameter of this aster is about 15 p.. Finally, there are immense 

 numbers of oxyeuasters which have only the tips of their rays microspined. 

 These latter asters have a total diameter of about 18 p., and have a greatly 

 varying number of rays. Some are only triaxons, others tetraxons ; but some 

 had as many as eight or even nine rays. 



B 



Text Figure No. 156. Spicules of Dorypleres splendens. A: Larger oxea, X 182. B: 

 Smaller oxea, X 182. C: Chiaster, X 782. D: Microspined euaster, X 782. E: Triact, 



X 782. 



