DESCRIPTION OF THE PLATES. 



PLATE I. 



Fig. 1. Chrysotile interlamellated with serpentine. Colafirth, Shetland. 



Fig. 2. Lamellated ophite (" Eozoon Canadense"), consisting of layers of 

 serpentine and calcite in parallelism with one another. Canada. 



Fig. 3. Peridote (olivine) enclosing fibrous or striated laminae. Elfdalen 

 in Dalecarlia. 



Fig. 4. Feldspar enclosing fibrous or striated laminae. 



Fig. 5. Graphic granite, consisting of layers of feldspar (a) alternating 

 with others composed of quartz (6). The former are transversely intersected 

 by striated fibrous and striped laminae. Harris, Hebrides. Specimens of the 

 kind have been taken for a fossil related to " Eozoon Canadense " ! 



Fig. 6. Specimen in which there is a definite and parallel alternation of 

 reddish quartz and red feldspar, rivalling that of the lamellated variety of 

 "Eozoon Canadense." Astracan. 



Fig. 7. Transverse section of a crystal, presumed, from its cleavage, to be 

 augite ; an optical examination, however, shows that its substance is peri- 

 dotized. Vesuvius. 



PLATE II. 



Fig. 1. Chrysotile changing into' "the acicular varieties ; also the same 

 replaced by calcite (a) : the variety c answers to the " proper wall," and the 

 calcite to the " intermediate skeleton " of "Eozoon Canadense" Reichenstein. 



Fig. 2. Portion of specimen of t( Eozoon Canadense" Layer of chrysotile () 

 in parallel alternation with serpentine (b) on one side and calcite (c) on the 

 other. In the latter case the fibres at the upper surface of the layer of chry- 

 sotile are broken and pressed obliquely out of position, thereby forming a 

 thin lamina ; these fibres are more or less separated by films of calcite in- 

 tegrally connected with the overlying calcitic layer. Thus the lamina corre- 

 sponds to the " proper wall," and the latter part to the "intermediate skeleton." 

 (N.B. The layers of chrysotile and serpentine are in such position to each other 

 as to prove their genetic correlation : it is also noteworthy that on the margin 

 where the chrysotile is in immediate contact with the serpentine there is no 

 fibrous lamina with its fibres separated by calcitic interpolations.) Canada. 



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