NIAGAKA GEOTJP. 



129 



This coral occurs in the neighborhood of Schoharie, in the coralline limestone*, and in the 

 same band of limestone in Ulster county. 



Near Louisville, Kentucky, this coral is one of the most abundant fossils in the Cliff lime- 

 stone ; and as the Niagara limestone there comes in contact with the upper Helderberg, or 

 the Onondaga and Corniferous limestones of New-York, the true position of the fossil is not 

 always appreciated. 



I have collected fine specimens of this coral, and in great abundance, in Iowa; and 

 have likewise received it from Wisconsin and Michigan, always holding the same geological 

 position. It is represented as abundant on Drummond island. Lake Huron, and is cited by 

 GoLDFuss from that locality. 



The wide geographical distribution of the species on this continent is very interesting ; and 

 it becomes more so, when we learn that in Europe it is also very extensively distributed, being 

 cited from Dudley, Wenlock, and other localities in England ; from the shores of the Baltic, 

 Gothland ; near Moscow, Russia ; and the Eifel, Germanyf . {State Collection.) 



518. 2. CATENIPORA AGGLOMERATA. 



Pl. XXXV. Fig. 2 a - g. 



Catenipora agglomerata. Hall, Geol. Rep. of 4th Dist. N. York, 1843 : Tables of fossils, no. 22, 



fig. 2. 



Coral consisting of cylindrical tubes, arranged laterally in a continuous series forming 

 broad explanate expansions, which are closely arranged in parallel, straight, or more or less 

 curving lines ; openings of the cells circular, tubes cylindric ; septa numerous, concave from 

 above ; spaces between the tubes cellular ; exterior surface somewhat transversely striated. 



This species contrasts with the preceding in the circular openings and cylindrical form of the 

 tubes, while it shows no tendency to assume the reticulated arrangement so characteristic of 

 that one. It appears as if made up of expansions of a single series of tubes, which are then 

 folded one against the other, sometimes in close parallel lines more or less curved and fre- 

 quently irregular, as if a regular series of foldings had been crushed laterally. In rare instances, 

 a single tube may be detected intercalated between two series or lines of tubes, uniting them. 

 The septa are very numerous, and sometimes scarcely more than their thickness asunder, always 

 bent downwards or concave. Transverse sections of the mass often present, upon the lower 

 side, the prominent convex surface of these septa. 



* See note page 107. 



t Its geological position in Europe appears not to be as constant as in this country, though it is easy to see how in 

 England it may be referred to the upper part of the Caradoc formation, when the Pentamerus oblongus is placed in 

 the same position, while both these fossils are remarkably typical of the Clinton group of New-York, which is 

 unquestionably upper Silurian. 



[Palaeontology — Vol. ii.] 17 



