242 



THE SPONGES OF THE WEST-CENTRAL PACIFIC 



Text Figure No. 166. Spicules of Cinachyra aiistraliensis, X 782. A: Outer end of the 



oxea. B: Cladome of anatriaene. C: Cladome of a somewhat abnormal protriaene. 



D: Inner end of a thin spicule, perhaps oxeote, probably a triaene. E: Inner end of an 



oxea. F: Two of the sigmaspires. 



The surface is conspicuously hispid. The pores are in poral calyces about 

 3 by 6 mm in lateral dimensions and 4 mm deep. These are usually (but not 

 quite always) arranged in an equatorial placement around the sponge. The 

 oscules are contractile and difficult to notice, but in No. M. 418 a large oscule 

 could readily be made out in the freshly collected specimen. This was on the 

 middle of the upper surface. It attained a diameter of more than 1 cm, and 

 branched immediately into a number of subdermal canals, about 2 mm in 

 diameter, so that it might almost be regarded as a cloaca, receiving these 

 oscules. 



The ectosome is a cortex nearly 1 mm thick ; the endosome is pronounced- 

 ly radiate. 



The skeleton consists of exceedingly long oxeas up to at least 34 jx in 

 diameter and at least 7 to 9 mm in total length. There are also fairly numerous 

 anatriaenes with clads, about 6 /x by 50 fx, and rhabds, 5 /x to 10 fx in diameter 

 and 1 or more mm long. In No. M. 207, a few protriaenes could be found, 

 with clads up to 10 p. by 60 [x and rhabds 10 jx by more than 1000 /x. The 

 microscleres include microxeas or raphides, 1.5 jx by 150 jx, and sigmaspires, 

 14 [x to 20 /x in chord length. These are less than 1 /x in thickness and are only 

 ultramicroscopically roughened. They are not so pronouncedly contorted or 

 spiral in shape as are those in the preceding species. 



This sponge was originally described as Tethya cranium, variety aiistral- 

 iensis, by Carter, 1886, page 127. It was first treated as a species, called 

 Tetilla aiistraliensis, by Sollas, 1888, page 43. It was correctly transferred 



