48 PLATE XIX. 



DICTYOCYLINDEUS HOWSEI, Bowerlank. 



Vol. ii, p. 106, ' Mon. Brit. Spongiadse.' 



Fig. 8. Represents a specimen of the species from 

 Douglas Bay, Isle of Man, expanded by immersion in 

 water to as nearly as possible its living condition. 

 Natural size. I received this specimen from Mr. 

 Howse. 



Fig. 9. A second specimen of the same species from 

 Douglas Bay, Isle of Man, expanded in water to nearly 

 its living condition. Natural size. In the cabinet of 

 the Rev. A. M. Norman. 



Fig. 10. A sub-fusiformi-acuate skeleton spiculum. 

 X 80 linear. This figure also represents the ex- 

 ternal defensive spicula. 



Fig. 11. Represents the basal portion of one of 

 skeleton spicula with a sub-spinulate base. X 80 

 linear. 



Fig. 12. An acuate slender tension spiculum. 

 X 80 linear. 



Fig. 13. One of the entirely spined, subclavated, 

 attennato-acuate internal defensive spicula from the 

 specimen presented to me by Professor Dickie. 

 X 250 linear. 



DICTYOCYLINDEUS VIEGULTOSUS, Bowerlank. 



Yol. ii, p. 113, 'Mon. Brit. Spongiadse.' 



Fig. 14. Represents three specimens of D.virgultosus 

 from Shetland in the cabinet of the Rev. A. M. Norman. 

 Natural size. The specimens were immersed in water 

 to restore them as nearly as possible to their conditions 

 before they were drawn. 



Fig. 15. An acuate skeleton spiculum. X 80 linear. 

 This figure also represents the large external defensive 

 spicula radiating from the axial skeleton. 



Fig. 16. One of the slender fasciculated external 



