266 PLATE LXXX. 



two tliirds of the leno-tli of the ous measured. The 

 spherical bases of these spicula are well produced. 

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

 whence it gTaduallyattenuates,terminatingvery 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 yl^ inch 

 in length, its greatest diameter near the base being 

 Tooo inch, while a small one did not exceed -3^ inch 

 in length. The tension sjoicula 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. 



