204 ANATOMY AND PHYSIOLOGY 



Dactylocalix. 



Skeleton siliceo-fibrous. Fibres solid, cylindrical. Reti- 

 culations unsymmetrical. 



Type, Dactylocalyx pumicea, Stutchbury. 



Mg. 274, Plate XV, represents the smooth variety of 

 fibre, with young fibres pullulatiag from the adult ones 

 at (ffl). Prom the skeleton of McAndrewsia azoica. Gray, 

 X 175 linear. 



Pig. 275, represents a portion of tuberculated siliceous 

 fibre from the skeleton of D. pumicea, Stutchbury, X 108 

 linear. 



Pig. 276, exhibits very prominently tiiberculated fibre 

 from D. Prattii, Bowerbank, MS. 



Pig. 340, Plate XXV, represents a small portion of the 

 skeleton of Iphiteon panicea in the Museum of the Jar din 

 des Plantes, Paris, with gemmules in situ, X 183 

 {Dactylocalyx, Stutchbury). 



Pig. 34 1 , a gemmule detatched from Ipldteon panicea, 

 X 666 linear. 



Suborder VII. Canaliculated siliceo-fibrous skeletons. 

 Skeletons reticulate, symmetrical. Pibres composed 

 of concentric layers of solid silex, with a continuous 

 central canal. 



Type, Farrea occa, Bowerbank, MS. 



I have seen in the organic remains from deep sea sound- 

 ings several varieties of fragments of siliceous fibres with 

 simple central canals, having every appearance of being 

 from unknown species of siliceo-fibrous sponges ; but the 

 only satisfactory specimen of this genus of sponges is the 

 one at the base of Dr. Arthur Parre's specimen of Euplec- 

 tella cucumer, Owen, described in the 'Transactions of 



