268 DicrYORPONoinvE. 



PLATE XXXV. 



PRISMODICTYA, gen. nov. 



Page 79. 

 (See Plate. XVII, XTIII, XIX, XX, XXI. XXVII, XXXIII, XXXIV, XXXVI, XLI, XLII, LV.) 



Prisjiodictya citiiaba, sp. nov. 



Page 90. 

 (See Plate XXXVI.) 



Figures 1, 2. Opposite sides of the same specimen, complete at the aperture 

 but imperfect toward the base ; showing the abrupt expansion of the 

 cup in the upper part of the sponge, with low nodes at the elevated 

 portions of the prism-angles. 



Figure 3. Another specimen showing similar characters. 

 Chemung group. Scio, Nev) Yofh. 



Pkismodictya nartiiecia, sjj. nov. 



Page 90. 



Figures 4, 5. Two views of the typical specimen, an elongate and slender 

 sponge \vith but slight expansion above the middle. 

 Chemung group. Scio, New YorK 



Pkismodictya choanea, sp. nov. 



Page 85. 

 (See Plates XIX and XXVII.) 



Figure 6. Fragment of a large individual with lo\v prism-faces (too strongly 

 rendered in the drawing). 

 Chemung group. Olean, JSfeio YorJe. 



Pkismodictya telum. Hall (sp.). 



Page 80. 

 (See Plates XVII and XLII.) 



Figures 7, 8. Two nearly entire specimens bearing low prism-faces and 

 showing the characteristic expansion of the frond near the base. 

 Chemung group. Friendship, New Yorlc. 



Pkisjiodictya paballela, Ilall (sp.). 



Page 82. 

 (See Plates XIX and XXI.) 



Figure 9. A part of a very long specimen showing little increase in diameter 

 throughout its length. 

 Chemung group. Hinsdale, New Yor7.\ 



