364 Intelligence and Miscellaneous Articles. 



blebs or granules imbedded like shot in the white calcite in a 

 manner quite similar to that of the chondrodite grains in the white 

 limestone from Amity, Orange County, in the same State. The 

 granules are not in all cases isolated, but sometimes occur in groups, 

 or connected by canals of serpentinous matter in a manner stri- 

 kingly suggestive of the detached sections and groups of Eozoon 

 chamberlets, as figured by Dr. Dawson on pages 24 and 28 of his 

 late paper*. Indeed I can but feel, since reading his resume, that, 

 even at this late day, this serpentinization of pyroxene is destined 

 to throw some light on the Eozoon problem. This idea is supported 

 by the fact that the fragmental Eozoon has been reported from 

 these same formations at Warren County, further by Dr. Dawson's 

 statement that eozoonal masses often occur as " rounded or dome- 

 shaped masses that seem to have grown on ridges or protuberances, 

 now usually represented by nuclei of pyroxene " t. While, from 

 the study of so limited an amount of the Warren County stone, it 

 may not be advisable to assert that the remarkably regular struc- 

 tures figured by Dr. Dawson are due wholly to alteration in situ of 

 pyroxene granules, I can but suggest that we have in this alteration 

 the source of the serpentinous material, and that the " mineral 



pyroxene of the white or colourless variety occurring often 



in the lower layers and filling some of the canals " of the Eozoon 

 is but the residual mineral which has escaped alteration. Further, 

 that the structureless nodules of serpentine found in the eozoonal 

 rocks, and to which often patches of Eozoon are attached or im- 

 bedded, are but patches in which the alteration is complete and the 

 pyroxenic nucleus quite obliterated. Dr. Dawson, although recog- 

 nizing the frequent accompaniment of a white pyroxene with the 

 eozoonal structure, in no case mentions appearances indicating 

 that the serpentine is an alteration-product, but seems rather to 

 regard it as an original injection J, following in this respect the 

 well-known teachings of Dr. Hunt§. Those conversant with the 

 literature of the subject may recall that Messrs. King and Rowney || 

 recognized also the presence of pyroxenes in these limestones, and, 

 in insisting upon the inorganic nature of the Eozoon, compared its 

 structural forms to those assumed by chondrodite, coccolite, &c. in 

 the limestones of New York, New Jersey, and other localities. 

 These authorities seem, however, to have regarded the serpentine 

 as true " replacement pseudomorphs " after these minerals rather 

 than alteration or metasomatic products. 



* " Specimens of Eozoon Canadense and their Geological and other 

 relations." Peter Redpath Museum. Notes on Specimens, Sept. 1888. 



t Op. cit. p. 29. 



X Op. cit. pp. 16-22 et als. 



§ Quart. Journ. Geol. Soc. of London, vol. xxi. p. 67 ; Chem. and Gaol. 

 Essays &c. 



II Quart. Journ. Geol. Soc. of London, vol. xxv. p. 115 ; also Proc. 

 Royal Irish Academy, vol. x. part iv. (1870) p. 606. 



