Spkcies ok the CiiKMUNfi Gijour. 137 



Dimensions. Length 145 mm.; diameter at the base 53 mm., at the 

 aperture, 160 ram. 



Locality. In the lower part of the Chemung group at Cotton hill, one 

 mile north of Avoca, Steuben county, N. Y. (Collection of E. B. Hall.) 



Arystidictya nodifeba, sp. nov. 



Plate xli, Fig. 11. 



In this species the ciip expands somewhat more regularly than in A. 

 elegans, and is of smaller size. Its surface is covered with low, vertically 

 elongate nodes which appear to be without definite order; these are larger 

 toward the base and become small and obscure toward the aperture, the 

 region about the apertural margin being smooth. This margin is smooth, unin- 

 terrupted, thin and regidar. 



This is an interesting species, but is imfortunately known only from a 

 part of a cup representing probably about one-half the original wdth. 



Locality. In the lower part of the Chemung group at Cotton hill, near 

 Avoca, N. Y., associated with A. elegans, Hydnocera-s tuberosum, H. multino- 

 dosrnn, H. eutJieles and Hallodictya Cottoniana. (Collection of E. B. Hall.) 



HYPHANT^NIA, Vanuxem (emendata). 



1842. JJphantenia, Vanuxem. Geology of New York; Kept. Third Dist., 



p. 184, fig. 50. 

 1863. UphantcBnia, Hall. Sixteenth Ann. Rept. N. Y. State Cab. Nat. Hist. 



pp. 84-87. 



The remarkable bodies to which the term UpiiANTiENiA has been long 

 applied, are very large, circular and shallow saucer-shaped cups, composed of 

 two series of intersecting spicular straps, one radiating from a common center, 

 the other concentric about the same point. The example which was described 

 by Vanuxem under the name Uphantenia Oliemungeiisis was a flattened quad- 

 rant, the original circular form of which was only inferential ; but specimens 

 of the species since found show the aperture of the cup to have been circidar. 

 In shape it appears to have been slightly elevated at the basal point, thence 

 outward to have curved gently downward and then upward again toward the 

 apertural margin. This at least is the foma presented by what seem to be 

 internal casts, from the sandstones of the Chemung group. The peculiar 

 feature of this shape, however, is the upward or inward projection of the apex 

 or base of the sponge. In the two specimens in which this part of the cup is 



