152 



serving a faithful likeness of such valuable specimens, 

 whenever it might be necessary to send them to a distance, 

 exposing them to the contingencies of travel. 



December 3, 1851. 

 The President in the Chair. 



Mr. Teschemacher exhibited a specimen of Anthracite 

 coal, containing a flattened branch of Stigmaria, one foot in 

 length, and three inches in diameter, with the usual mark- 

 ings of the cicatrices of foliage, two of which were very 

 perfect. 



He remarked that the knowledge hitherto promulgated of this 

 fossil plant, so abundant in all the coal formations, had been 

 chiefly obtained from specimens in the coal measures, but not 

 from those in the coal itself; and that the opinions of its affinity 

 to the families of plants of the present day varied much. The 

 doubts respecting its nature he thought could only be dispelled 

 by instituting close comparisons, and this he proposed to do 

 between what was already known on the subject, the fossil spe- 

 cimens on the table, and our well-known native tree Picea hal- 

 samiferay of which he exhibited fresh specimens. 



1. The cicatrix of the leaf, as shown in the perfect specimens 

 on the coal, when examined with a good Coddington lens, agrees 

 minutely with those of Picea, except in size, the fossil being one 

 eighth, the recent, one sixteenth of an inch in diameter; the 

 cicatrices of Picea are persistent even on old wood. 



2. The form of the leaf of Stigmaria, as given in figures in 

 the various publications, is linear, with an obtuse termination, a 

 midrib, and thickness at the edges, produced by involution of 

 margin ; such, also, is the leaf of Picea. 



3. In the fossil, the leaf is sessile, or without petiole, as in 

 Picea. 



