1866.] KING AND ROWNEY " EOZOONAL ROCK." 199 



is sustained by many of the pseudomorphic phenomena made known of late 

 years by Bischof, Breithaupt, Blum, Daubree, Delesse, Fallou, Fournet, Miiller, 

 G. Eose, and others. 



We offer this hypothesis to explain the intermixture of flocculent matter and 

 calcite, which occurs so commonly in the so-called skeleton of " Eozoon" and 

 the change of the surfaces of its " chamber-casts " into chrysotile and flocculent 

 matter ; also to account for the occasional absence of the latter two substances 

 from the surfaces of the "chamber-casts," and their replacement by calcite: in 

 short, we offer it in explanation of most of the cases of isolated aciculi, rods, 

 bundles, and patches of the asbestiform layer and the fillings in of their separating 

 spaces by calcite. 



y. " Canal-System " of " Eozoon Canadense." 



Although feeling it necessary to relinquish the idea of the " asbes- 

 tiform layer " having been originally an organic structure, we still 

 adhered for some time afterwards to the foraminiferal origin of 

 Ophite. But having made, as we conceived, an important recti- 

 fication in the diagnosis of '' Eozoon Canadense,^^ we naturally felt 

 ourselves stimulated to endeavour to elucidate the " canal-system,'' 

 which it was considered had in certain instances been confounded 

 with " stolon-passages." 



It is unnecessary for us to give a history of our investigations 

 into the speciality now entered upon ; suffice it to say that the 

 longer we examined the more our opinions became unsettled. 

 Something new was continually turning up to the prejudice of the 

 behef we had firmly and tenaciously adhered to ; so that at last we 

 found ourselves under the necessity of completely abandoning a point 

 which had often proved a sheet-anchor whenever either of us .was 

 losing ground in our mutual discussions*. 



Lying in the decalcified passages of both Canadian and other 

 varieties of " eozoonal " Ophite, of the Connemara variety especially, 

 there are frequently seen irregularly shaped "amorphous masses" 

 of a mineral substance slightly compact in texture, of a milk-white 

 colour, and lustreless like starch. Neither Dawson nor Sterry Hunt 

 has alluded to them ; and Carpenter, by whom they appear to have 

 been overlooked at first, has only briefly described the Canadian 

 examples in his last paper, published in the ' Intellectual Observer.' 

 He finds them "to consist in some instances of parallel lamellge, 

 disposed like the leaves of a book, and in others of solid bunches of 

 rounded filaments, reminding one of a sailor's ' swab.' " The Cana- 

 dian examples are apparently more compact in texture than the 

 Irish. When detached and crushed, a quarter-inch object-glass 

 discloses in the former a more or less granular, and in the latter a 

 somewhat fibrous structure. 



Besides the foregoing, there are present, especially in Grenville 

 Ophite, the simple and branching structures noticed in the early 

 part of this memoir, or, as they have been named, " definite shapes," 



* As soon as we had become fully conyinced that all the parts of " Eozoon 

 Canadense " were of mineral or crystalline origin, we announced the circum- 

 stance in one of the weekly periodicals, promising at the same time to lay before 

 the public at an early opportunity the various evidences and considerations 

 which sustained us in our views. (See ' Header,' June 10, 1865, p. 660.) 



