1866.] KING AND EOWNEY— " EOZ0ONAL EOCK." 217 



EXPLANATIONS OF PLATES XIY. & XV. 



Illustrative of the view of the inorganic nature of Eozoon. 



Plate XIV. 



Fig. \. Section, viewed as an opaque object, of a portion of a granule (" chamber- 

 cast") of serpentine, having one edge, facing a decalcified passage, 

 furnished with two asbestiform layers. The inner layer is perfectly 

 compact, except at the left end ; the outer one has the fibres in the 

 left half standing apart, but in the right half they are in close contact. 

 The outer layer is nearly separated from the inner one. The granule 

 is green and translucent ; the layers are white and vitreous. Mag- 

 nified 210 diameters. From Grenville. 



2. Section, viewed as an opaque object, embracing a lobulated granule of 



green serpentine, and a portion of its matrix (lower part), com- 

 posed of white saccharoidal calcite ; the specimen is not decalcified. 

 The striated portion represents the asbestiform layer (" pseudopodial" 

 or " proper wall"), which is perfectly compact, except at the places 

 marked a and h, in which the fibrous structure is in an intermittent or 

 incipient state of development. The peculiarities of its structure show 

 that the layer is an integral portion of the serpentine. Magnified 210 

 diameters. The specimen has been examined with a power of 350, 

 with the same result. From Grenville. 



3. Section, viewed as a transparent object, of three granules of serpentine 



(" chamber-casts"), with their edges notched or broken up into sepa- 

 rated bundles of asbestiform fibre. The interspaces between the 

 bundles, as well as those between the granules, are filled with flocculent 

 matter. Our view of the specimen is, that the spaces between the 

 bundles of asbestiform fibre originally consisted of serpentine, which has 

 been converted into flocculite ; also, that possibly the entire mass of the 

 latter between the granules was once serpentine. Magnified 120 dia- 

 meters. The specimen has also been examined as an opaque object, 

 under a power of 350, with the same result. From Grenville. 



4. Section, viewed as an opaque object, representing a small portion of a 



long fissure, which intersects a number of granvles of serpentine. One 

 of the walls of the fissure is crowded with aciculi {identical with 

 "casts of pseudopodial tubuli" of ^^ Eozoon Canadense"), separated, 

 as well as in close contact : in a few places the acicidi form bundles ; 

 see centre of the lower wall. The upper wall is crowded with a very 

 thin asbestiform layer. Magnified 1 10 diameters. From Lisoughter. 



5. Section, viewed as an opaque object, of a portion of asbestiform layer 



{identical with that of ^'■Eozoon Canadense''), lying between, and 

 attached to, two grains of yellowish-brown chondrodite. In the left 

 half, the layer, which is white, translucent, and silky, is perfectly 

 compact ; but in the other half, its fibres are in some places separated 

 and a little twisted. Magnified 120 diameters. From New Jersey. 



6. Section, viewed as an opaque object, of grains of chondrodite separated 



by an asbestiform layer, the fibres of which are here and there apart, 

 and in some places not strictly parallel. Magnified 60 diameters. 

 From New Jersey. 



7. A grain of chondrodite, viewed as an opaque object. It is furnished at 



one end with the remains of an asbestiform layer, the fibres of which 

 form slender aciculi ; or, in other words, the aciculi are composed of 

 asbestiform fibre. The vacant spaces appear to have been occupied by 

 fibres or aciculi, which, through some cause have disappeared. Mag- 

 nified 120 diameters. From New Jersey. 



8. Section, viewed as an opaque object, of a granule ("chamber-cast") of 



serpentine, showing a fringe of asbestiform layer ("tubulated proper 

 wall"), which generally consists oi parallel fibres; but in some places 

 the fibres are divergent. In one place the layer is replaced by a coat 

 oi flocculite. It is our opinion that the latter has resulted from a 

 change either of the asbestiform layer or of the serpentine. Magnified 

 VOL. XXII. PAET I. E 



