78 



THE SPONGES OF THE WEST-CENTRAL PACIFIC 



yA— . ■ ■ ■ ■ . . • ' . 



Text Figure No. 47. Cribrochalina olcmda. A: Portion of one of the fascicular fibers, 

 X 182. B: Portion of the network of simple fibers, X 182. C: One of the spicules 



(oxea), X 781. 



commonly about 6 cm but may be as large as 16 cm. The height may reach 

 as much as 40 cm, and specimens of over 30 cm are common. The walls of 

 the tubes are usually about 5 to 10 mm thick, some were found as thin as 

 4 mm, and a few as thick as 20 mm. 



The interior and exterior color in life was a pale, but clear and beautiful, 

 blue. A few drab spots were probably pathological. The consistency was 

 very spongy, and this species is peculiarly sticky to the touch. It excludes 

 much slime, and this slime has a glue-like effect, being very difficult to wash 

 from the hands. 



The surface is tuberculate, with tubercles about 1 mm high and 3 mm 

 apart on centers. When the sponge is dry, these shrink until they become 

 conules. There are skeletal pores about 500 fi in diameter and about one 

 for each 4 square mm of the surface. These in turn are subdivided into actual 

 pores which are only 50 fx to 80 ii in diameter and are about 100 t<, to 200 p. 

 apart, center to center. The canal system of this sponge opens into the large 

 cloaca, through holes or openings which should be called apopores ; these 

 are abundant, about 1 to 4 mm in diameter and 3 to 5 mm apart. It is fairly 

 clear that all the inhalant apertures are on the exterior of the tube and that 

 the exhalant ones lead on out through the cloaca. 



The ectosome is somewhat unusual for one of the Haliclonidae, inas- 

 much as there are subdermal spaces. These are roofed over, however, by a 

 dermis which is exclusively protoplasmic, containing no skeleton. The endo- 

 some is fibro-reticulate. 



The skeleton comprises oxeas, 2 /x by 92 fi to 3 /x by 100 n in dimen- 

 sions. Most of these are located inside the fibers, which range from 12 fx to 

 25 /x in diameter and often intersect at approximately right angles. In addi- 



