Explanations ok Plat*s. 241 



IIYDRIODICTYA, gen. nov. 



Page 77. 

 (See Plates IV, V, XVI, LV.) 



IIyduiodictya nki'iielia, 8|). nov. 



Page 79. 



Figure 10. An incomplete specimen shomng what appears to be the 

 expanded apertural part of a vase-shaped cup with subprismatic 

 faces. 

 Cemung group, Scio, New YorJc. 



CLATimOSPONGIA, gen. nov. 



Page 121. 

 (See Plates XIV, XV, XVIII, XXI, XXV, XLIX, L.) 



ClATHBOSPOKGIA (?) TOMACULUM, Hall (sp.). 



Page 123. 



(See Plate XVIII.) 



Figure 11. A sharply defined cast of a portion of the exterior showing the 

 character of the quadrulation. 

 Chemung group. Alfred, N Y. 



Clathbospongia vascellum, Hall (sp.). 



Page 123. 

 (See Plate XXV.) 



Figure 12. The opposite side of the specimen shown on the plate cited. 

 This surface exhibits traces of very coarse primary vertical spicular 

 ridges and in places shows some of the finer reticulation. 

 Chemung group. Alfred, N. Y, 



