PLATE VI. 



PAGE 



Figs. 1, 2. Eaplectella oweni, Marshall and Herklots, . . 78 



Fig. 1. A portion of the iuner layer of the lateral wall of a young dried specimen 

 of Euplectella oweni, Marshall and Herklots ; natural size. 



Fig. 2. Spicules from the margin of a parietal gap ; x 40. 



Fig. 3. Euplectella suhei'ea, Wyv. Thomson, . . 73 



Fig. 3. Section, at right angles through the lateral wall, of a specimen of 

 Euplectella suberea, Marshall and Herklots, preserved in alcohol 

 with the soft parts ; x 10. 



Figs. 4, 5. Euplectella jovis, 0. Schmidt, . , .77 



Fig. 4. A portion of the inner layer of the side wall of a dry specimen of 

 Euplectella jovis, 0. Schmidt; natural size. 



Fig. 5. Spicules of the margin of a parietal gap ; x 40. 



