1848.] BUNBURY ON FOSSIL PLANTS. 141 



Descriptions of Fossil Plants from the Col de Balme and other 

 places near Chamounix. 



1. Odontopteris Brardii. 



The same as from the Tarentaise. The leaflets are usually rather 

 less falcate and less acute than in Brongniart's figures, and it passes 

 by intermediate specimens into the next form. 



2. Odontopteris obtusa ? 



Identical with No. 5 of the preceding list, but I do not find in any 

 of the specimens from the Col de Balme that curious want of sym- 

 metry which is so striking in some of those from the Tarentaise. 



3. Neuropteris flexuosa (Brongn. Veg. Foss. p. 239, t. 68. f. 2). 



The specimens of this plant are well preserved and highly charac- 

 teristic, agreeing precisely with those from the coal-fields of North 

 America. The specimens in my collection were found, as I was told, 

 in the mountains above Servoz ; those which were shown to me by 

 M. Pictet, in the museum of Geneva, were from the mountains near 

 Martigny in the Valais. One fragment has the leaflets so broad and 

 round, that it might be referred to N. rotundifolia, but I have ob- 

 served a similar variation in English specimens ^i N. flexuosa. 



Neuropteris flexuosa is a very general and very abundant fossil in 

 the North American coal-fields, especially in those of Pennsylvania 

 and Cape Breton. In Europe it seems to be less frequent, but I have 

 seen specimens from Pembrokeshire and from Somersetshire, and it 

 is recorded from Bohemia. 



4. Neuropteris? 



Very like N. conferta of Goppert (Syst. Fil. Foss. p. 204, t. 40), 

 but the specimen is not perfect enough for satisfactory determination, 

 and in particular I cannot ascertain whether the main stem is winged 

 with decurrent leaflets, — one of the essential characteristic marks of 

 that species. I saw nothing similar to this among the specimens from 

 the Tarentaise. 



5. Neuropteris alpina (Sternb.) ? 



(Gopp. Syst. Fil. Foss. p. 204 ?) 



Several of the specimens from the Col de Balme seem to belong to 

 this species, though none of them are sufliciently perfect to display 

 its characters in a thoroughly satisfactory manner. It is very likely 

 that some of those from the Tarentaise, which I placed doubtfully 

 under N. tenuifolia^ may also belong to this, for, owing to the man- 

 ner in which the specimens are encrusted with talc, it is often diflS- 

 cult to determine whether the leaflets are really adnate to the rhachis 

 or not, and the venation is generally very obscure. Judging from 

 those examples in which the veins are best shown, I should think 

 that this species is not well placed in Neuropteris. 



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