140 



tinctions between the Saxon, Norman, and 

 English styles, and the gradual alteration of the 

 circular, sharp pointed, and flat arches. The 

 subject was entirely new to me, but I felt so 

 much interest"in it that he has promised here- 

 after to go through a little course of architecture 

 with me, from the Egyptian and Grecian to the 

 Roman and Gothic. 



. We were talking to-day about the im- 

 pressions of plants perceptible in coal, and I 

 asked my uncle to tell me what plants they 

 were ; he referred me to Miss Perceval, who 

 says that it appears from the researches of 

 several German botanists, and particularly from 

 those of Dr. Martius, that some of the Brazilian 

 plants, which are so familiar to us, dear mamma, 

 seem to have such a resemblance to those im- 

 pressions, that there can be scarcely a doubt of 

 their identity. 



" The tree ferns," she said,, " exhibit several 

 characters in common with those ancient plants ; 

 one species in particular, the stem of which 

 having a remarkable tessellated or chequered 

 appearance, exactly represents some of the 

 petrified forms found in the German coal 

 mines. Dr. Martius describes ten different kinds 

 of fern found in coal, each distinctly marked by 

 some of those peculiarities which distinguish the 

 living plants. 



