48 



About fonrteen feet of the stem have been exposed, and the thick- 

 est part measures three feet in diameter. The internal structure consists 

 of uniformly elongated cellules, with medullary rays or plates, and the 

 concentric circles, if any exist at all, are very indistinct. In the 

 transverse section, the woody tissue presents the appearance of a re- 

 gular radiating series of four-sided or subhexagonal cellules, with 

 the usual medullary lines intervening. Two of the walls of the elon- 

 gated cellules, those facing and parallel to the medullary plates, are 

 regularly reticulated with two, three, or more series of contiguous 

 subhexagonal areolae. 



The areolae in both Pence and Pitus are separated and roundish, 

 whereas in the Piniles they are subhexagonal and continuous. This 

 is the case with the fossil plant under consideration, which must 

 therefore be referred to the last mentioned genus. 



The constituents, according to an analysis by Dr Walker, are car- 

 bonate of lime 50.36, carbonate of iron 24.65, carbonate of magnesia 

 17.71> coal, silica, and a little water 6.15. 



February 17. 



JAMES RUSSELL, Esq. V. P., in the Chair. 

 The following Donations were presented : — 



History of the Berwickshire Naturalist's Club, instituted Sep- 

 tember 1831. — From the Cluh. 



Memoires de la Societe Geologique de France. Tome I. Part 1. — 

 From the Society. 



Memoires de la Societe de Physique et d"Histoire Xaturelle de 

 Geneve. Tome II. Part 2. Tomes III. & IV. — From the Society. 



Memoires de I'Academie Royale des Sciences de ITnstitut de 

 France. Tome XII. — From the Institute. 



The following Communications were read : — 



1. Analysis of Coprolites from the Limestone of Burdie- 

 House. By Arthur Conneli, Esq. 



These coprolites, as well as the limestone where they are found, 

 contain a trice of animal matter, as ammonia is disengaged at a red 

 heat. 



Muriatic acid dissolves the greater part with slight effervescence. 

 Ammonia throws down from the solution a copious gelatinous preci- 



