OP THE SPONGIAD^. 231 



Fig. 



18. PusiFORMi-ATTENUATO CYLINDRICAL. — Both termina- 



tions being hemispherical, the fusiform shaft has a 

 much smaller diameter towards its apex than it 

 has at its base. From Tethea robusta, Bower- 

 bank, MS. A new species from Australia, in the 

 British Museum. X 90 linear. 



19. BiCLAVATED CYLINDRICAL. — The shaft equally cylin- 



drical, with gradually inflated terminations. The 

 inflations are almost as great as that of a spinulate 

 spiculum, but without sphericity. From a new 

 and undescribed species from Australia, Bower- 

 bank collection. X 260 linear. 



20. Inequi-Biclavatbd cylindrical. — The shaft atten- 



uated from the base to the apex, with clavated 

 terminations of unequal diameters. From Pachy- 

 matisma Johnstonia, Bowerbank. X 90 linear. 



21. Angulated inequi-Biclavated cylindrical. — This 



singular angulated form does not appear to be 

 purely accidental, as I have found other instances 

 of similar angulation at the middle of the shaft in 

 other sponges, and the angle in each instance has 

 been as nearly as possible at the same spot in the 

 shaft. Pachymatisma Johnstonia, Bowerbank. 

 X 90 linear. 



22. Spinulate.-— Shaped like a pin, having the same 



diameter from the spherical base to very near the 

 acutely terminated apex. Hymeniacidon carnosa, 

 Bowerbank. X 260 linear. 



23. FusiPORMi-spiNTJLATE. — The base being spherical, 



the shaft more or less fusiform and terminated 

 acutely. Hymeniacidon suberea, Bowerbank. X 

 260 linear. 



24. Depresso-spinulate. — Having the basal inflation 



considerably depressed, the shaft having the same 

 diameter to very near the apex. From an unde- 

 scribed species of sponge from Ash Island. X 

 160 linear. 



