256 PLATE LXXX. 



two thirds of the length of the one measured. The 

 spherical bases of these spicula are well produced. 

 The thickest part of the shaft is close to the base, 

 whence it gradually attenuates, terminating very acutely. 

 The internal defensive spicula were rather numerous, 

 and were mostly in a more or less erect position, but 

 many of them were procumbent. They vary con- 

 siderably in size ; one of the largest measured -^ e incn 

 in length, its greatest diameter near the base being 

 g^j inch, while a small one did not exceed -^ inch 

 in length. The tension spicula are long and exceed- 

 ingly slender ; they are mostly dispersed singly amid 

 the sponge, but occasionally a few of them occur 

 together in a loose fasciculus. 



