210 UlC'TYoSl'UiNOlD.E. 



PLATE VI. 

 HYDNOCERAS, Conrad. 



Pagfi 95. 

 (See Plate. II, UI, IV, V, VII, VIII, IX, X,XI, XII, XXXIII, XXXVI, XXXVII, XXXVIII, XXXIX, XLVI.) 



Hydnoceeas antiiracis, sp. nov. 



Page 109. 

 (See Plates II, XXXIII.) 



Figure 1. A view of the upper portion of an individual, showing the small 

 size of the species, its prismatic form, broad and smooth apertural 

 surface and subcircular nodes. On the right of the specimen the 

 extension of these nodes and their tufts into the matrix is shown. 



Figure 2. The opposite side of the same specimen. 

 Chemung group. Scio, Neio York. 



Hydnoceras tuberosum, Conrad. 



Page 97. 

 (See Plates II, in, IV, V, VU VIII, XXXVIII.) 



Figure 3. Two small individuals in a block of sandstone which retains 

 impressions of the spicular tufts and lamellae. 

 Chemung group. Brown hill, 'near Cohocton, New Yorh. 



Hydnoceras phymatodes, sp. nov. 



Page 104. 

 (See Piute XXXVII.) 



Figures 4, 5. Opposite sides of a typical specimen having seven horizontal 

 rows of low nodes ; in the second and third rows there being eight 

 nodes, in the fourth, nine, in the fifth and sixth, eleven. In the fifth 

 horizontal row in figure 5, an intercalary node begins a new vertical 

 row. 

 Chemung group. Bath, New Yorh. 



