541 



happened to the efforts of both Drs. S terry Hunt and Carpenter to 

 explain a " process" which cannot but be regarded as " of primary im- 

 portance in the main question under discussion?" 



5. Geological Considerations. 



It will seem strange to many, after reading the statement in our 

 former Paper of several specimens of Connemara ophite having passed 

 under our notice, possessing the characteristic " eozoonal" features more 

 or less combined, and as perfectly preserved as in Canadian examples, 

 that this rock should be referred to, as having only " a partial analogy 

 to that of Canada" (Carpenter), and as being a " disputed case" (Daw- 

 son). If necessary, we could fill a Plate with examples, from our locality, 

 of the " asbestiform layer," arborescent and other " definite shapes," not 

 surpassed by any that have been figured, from Petite Nation or elsewhere, 

 in their seeming resemblance to the " cell- wall" and " canal system" 

 of a nummuline foraminifer, and associated with " acervuline chamber 

 casts," exactly as in " Eozoon Canadense." Indeed, the Connemara 

 ophite, with such examples, is more typically " eozoonal" than the 

 accepted variety from Bavaria, if the latter contain no better marked 

 " foraminiferal features" than have been detected in it by Dr. GiimbeL 



In our former communication, referring to the Isle of Skye ophite, 

 which is indisputably Liassic in age, we stated that "no doubt can be 

 entertained as to its eozoonal" character — a statement which may be 

 considered to be sufficiently borne out by our describing it as containing 

 4< ' chamber casts' occasionally invested with the 'proper wall,' " and 

 " thickish dendritic aggregations :" the latter, it might be understood, we 

 considered to represent " the canal system."* Yet Dr. Dawson sets 

 aside our statement respecting these features by asserting that this rock 

 " is admitted" (by whom ?) "to fail in essential points of structure" ! It 

 has thus become absolutely necessary for us to give a representation of the 

 " eozoonal" characters of the Isle of Skye ophite, which we have done in 

 Fig. 10 (PI. XLIY.), magnified 210 diameters, taken from a portion of a 

 decalcified specimen. The " chamber casts" (A, Ax), it will be seen, are 

 furnished with an " asbestiform layer" (d), as much a "true cell wall" as 

 any examples occuring in the Canadian rock ; and consisting of separated 

 and juxtaposed aciculi — parallel and divergent. Owing to the specimen 

 having been ground down to produce a level surface, most of the 

 "chamber casts" have been cut across, which causes the "nummuline 

 layer" investing them to appear as if " bordered with a delicate white 

 glistening fringe ;" but below the plane of this surface there are two 

 "chamber casts" (Ax), which, when properly focussed, are seen to have 

 their entire surfaces completely "hispid" with aciculi, forcibly reminding 

 one of the recent siliceous casts of Amphistegina described by Dr. Car- 

 penter. 



* "Quarterly Journal of Geological Society," vol. xxii., p. 204. 



