540 DR. J. E, GRAY ON SPONGES. [May 9, 



Okina angulata. 



Halichondria angulata, Bowerb. ib. ii. p. 233. 



VI. Defensive spicules regular, birotulate, with many rays at each 

 end, free in sarcode. 



31, Carteria. 



Sponge massive, irregularly reticulated, shallow, formed of abundant 

 agglutinated filiform needle-like spicules, with four- and six-rayed 

 stellate, cruciform, and birotulate spicules. 



Hyalonema, part., Bowerb. ; Schultze ; Brandt (not Gray). 



Carteria japonica. 



Hyalonema mirabiUs, Bowerb. B. S. i. p. 237, f. 60-65 ; p. 276, 

 f. 294, 295 ; Schultze, t. 3 & 4 (not Gray). B.M. 



Hab. Japan. 



Bowerbank's figures (Br. Sp. 153-157) represent the spicules of 

 the corium that surround the filaments of Hyalonema inirabilis, 

 Gray, and have nothing to do with the smooth stellate or radiate spi- 

 cula of this sponge. They have been called Spongia octancyrce, 

 Brandt, Ilyal. p. 14 ; Spongia spinicruces, Brandt, Hyal. p. 23, t. 3, 

 f, 15, 16. They are also figured in Schultze's 'Hyalonema,' t. 3. 

 f. 9-14. 



Fam. 3. Tethyad^. 



Sponge massive, suborbicular or subramose, fleshy. Skeleton con- 

 sisting of simple fusiform and of fusiform spicules with three prongs 

 or three diverging hooks at the distal or outer extremity, and with 

 more or less globular many-rayed stellate spicules, or of either of 

 the two kinds. 



The stellate spicules are composed of few or many radii, emanating 

 from a centre in all directions. Their simplest form is when the bases 

 of the radii all proceed from a common point ; in others the radii 

 S})ring separately and distinctly from a common central spherical or 

 oval base.— Bowerb. Phil. Trans. 1858, p. 307, 309. 



Dr. Bowerbank calls the elongate spicules which are peculiar to 

 Geodiadce and Tethyadae connecting spicula. These spicula have a 

 long, stout, cylindrical, or attenuated shaft, terminating either 

 acutely or hemispherically at the base ; while the apex is divided 

 into three stout equiangular radii, which assume in different species 

 a considerable variety as regards form and direction. The triradiate 

 apices are usually cemented firmly to the inner surface of the crus- 

 tated coat of the sponge ; while the stout and elongated shaft is in- 

 termingled with and firmly cemented by keratode to the general mass 

 of the skeleton. The triradiate apices also serve to construct areas 

 in which are situated the proximal orifices of the intermarginal cavi- 

 ties, which are imbedded in the crustated surface of the sponge. — 

 Bowerb. Phil. Trans. 1858, p. 289. 



