IN THE STRATA OF THE LIAS AND OOLITIC SERIES. 67 



Fig. 9- Represents a portion of the Lennel Braes' plant figured in Plates 

 III, IV, VII, and VIII. The fragment of organic structure at the upper 

 corner is silicified and very regular. It presents the appearance of a line 

 of junction of two concentric layers. This figure is of the natural size. 



Fig. 10. The margin of the fragment indicated above, enlarged about 

 fifty-five times. This figure displays the beautiful lace-like structure, 

 broken up at the edge by calcareous spar, of which two divergent crystal- 

 lizations are seen. 



Fig. 11. Fossil silicified dicotyledonous wood, from Antigua, enlarged 

 about fifty-five times. The structure greatly resembles that of the Maho- 

 gany, represented in Plate I. Fig. 10. 



Fig. 12. Fossil silicified dicotyledonous wood, from Antigua, enlarged 

 about fifty-five times. 



Fig. 13. Fossil silicified dicotyledonous wood, from Antigua, enlarged 

 about fifty-five times. The calcedonic mode of crystallization is observed 

 at the lower part of the figure. 



Fig. 14. Fossil silicified wood, from Antigua, probably dicotyledonous, 

 and resembling Fig. 13. of Plate I. 



On comparing Figs. 11, 12. 13, and 14 of this plate, with Figs. 10, 11, 

 12 and 13 of Plate I., it will be seen that the general resemblance is per- 

 fect. 



Figs. 15. and 16. Represent portions of silicified monocotyledonous 

 wood from Antigua, and may be compared with Figs. 14 and 15 of Plate 

 I, which exhibit the same structure. They are enlarged about fifty-five 

 times. 



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