OF THE SPONGIADiE. 237 



Pig. 



58. SprctJLATED poauECTo-TERNATE. — ^Having three equi- 

 distant porrect terminal rays, and a fourth or 

 central one in a line with the asis of the shaft. 

 Prom Geodia Barretti, Bowerbank, MS, X 90 

 linear. 



PREHENSILE SPICULA. 



59. Apically spined recbrvo - qpaternate. — From 

 BuplecteUa cucumer, Owen. X 90 linear. Pro- 

 jected from the basal portion of the sponge as a 

 means of attachment to other bodies. The recurvo- 

 quaternate end (a) being the apex of the spieulum. 

 Page 20. 



DEl'ENSIVE SPICULA. 



60. MuLTiDENTATE BiROTULATE. — Hyalomma mirahilis. 



Gray. X 83 linear. This form is more especially 

 a retentive spieulum ; an auxiliary to the oJBFensive 

 and defensive spiculated cruciform spicula with 

 which it is associated in the interstitial cavities of 

 the sponge. Pig. 294. 



Prom the basal portion of a specimen in the British 

 Museum. Pages 37 and 127. 



61. Elongo-recurvate dentato-birotulate. — ^Fromthe 



same sponge as Fig. 60. X 308 linear. 



62. Recurvo - acutely dentate - birotulate. — From 



soundings in the Indian Ocean, 2200 fathoms; 

 probably from an unknown species of Hyalonema. 

 X 308 linear. 



63. Elongo-recurvate dentato-birotulate. — From 



soundings in the Indian Ocean, 2200 fathoms; from 

 most probably an unknown species of Hyalonema. 

 X 308 linear. 



