290 DlCTYOSPONGID^ 



PLATE XI. 

 HYDNOCERAS, Conrad. 



Page 95. 

 (Se« Plates H, HI, IV, V, VI, VII, VHI, IX, X, XII, XXXIII, XXXVI, XXXVII, XXXVIH, XXXIX XLVl.) 



Hydnoceras Avoca, sp. nov. 



Page 103. 

 (See Plates II, IX and X.) 



Figure 1. This specimen represents the apertural and upper portion of a 

 gigantic individual of this species, whose probable original propor- 

 tions are partially restored in outline. The sponge is somewhat 

 irregularly compressed, and the nodes upon its surface have been flat- 

 tened without destroying their characteristic expression m this 

 species. The specimen was taken from the foundation wall of an old 

 mill at Avoca, and its exact locality is not known, though doubtless 

 from the beds in that vicinity which have produced most of the 

 known examples of this species. 

 Chemung group. Avoca, New Yorh. 



