94 PLATE XXXVIT. 



RAPHIODESMA FLOEEUM, Bowerbank. 



Hymeniacidon floreum. Vol. ii, p. 190, ' Mon. Brit. Spon- 



giada3.' 



Fig. 14. Represents the type-specimen from East 

 Loch, Tarbet Harris, N.B., presented to me by Capt. 

 F. W. L. Thomas, R. N. Natural size. 



Fig. 15. One of the skeleton spicula. X 250 

 linear. 



Fig. 16. A subclavate, fusifonni-acerate, tension 

 spiculum from the dermal membrane. X 250 linear. 



Fig. 17. One of the large dentate-palmate, inequi- 

 anchorate, retentive spicula. X 530 linear. The 

 mode of the congregation of these spicula is repre- 

 sented in vol. i, plate xviii, fig. 297, as they occur in 

 Hymeniacidon lingua of that volume. 



Fig. 18. One of the bidentate, inequianchorate, 

 retentive spicula. X 530 linear. 



Fig. 19. - - A large contort, bihamate spiculum. 

 X 530 linear. 



This sponge was figured among the Hymeniacidon s 

 before I had established the genus Raphiodesma for 

 the reception of R. lingua and R. sordida, to both of 

 which species R. floreum is closely allied by its struc- 

 tural peculiarities. 



HYMENIACIDON CLAVIGERA, Bowerbank. 



Vol. ii, p. 211, ' Mon. Brit. Spongiadse.' 



Fig. 20. Represents the type-specimen in the 

 cabinet of the Rev. A. M. Norman. Natural size. 



Fig. 21. One of the large, attenuato-clavate, or 

 spinulate, skeleton spicula. X 80 linear. 



Fig. 22. An attenuato-clavate, entirely-spined, 

 internal, defensive spiculum. X 250 linear. The 

 spination of the shaft of this spiculum has been acci- 

 dentally omitted. 



