CONTEMPOEAEIES AND SUCCESSORS OF EOZOON. 147 



cliondrodite, rosellan, garnet^ and scapolite, arranged 

 in bands. In several places the lime is mingled with, 

 serpentine, grains or portions of which, often of the 

 size of peas, are scattered through the limestone with 

 apparent irregularity, giving rise to a beautiful variety 

 of ophicalcite or serpentine-marble. These portions, 

 which are enclosed in the limestone destitute of ser- 

 pentine, always present a rounded outline. In one 

 instance there appears, in a high naked wall of lime- 

 stone without serpentine, the outline of a mass of 

 ophicalcite, about sixteen feet long and twenty-five 

 feet high, which, rising from a broad base, ends in a 

 point, and is separated from the enclosing limestone 

 by an undulating but clearly defined margin, as al- 

 ready well described by Wineberger. This mass of 

 ophicalcite recalls vividly a reef-like structure. With- 

 in this and similar masses of ophicalcite in the crystal- 

 line limestone, there are, so far as my observations in 

 1854 extend, no continuous lines or concentric layers 

 of serpentine to be observed, this mineral being al- 

 ways distributed in small grains and patches. The 

 few apparently regular layers which may be observed 

 are soon interrupted, and the whole aggregation is 

 irregular. ^^ 



It will be observed that this acervuline Eozoon of 

 Steinhag appears to exist in large reefs, and that in 

 its want of lamination it differs from the Canadian 

 examples. In fossils of low organization, like Forami- 

 nifera, such differences are often accidental and com- 

 patible with specific unity, but yet there may be a 



