296 DESCRIPTION OF THE OXIDE OF TIN 



It is interesting to know that the Ttrniopteris vittata is one of 

 the characteristic fossils of the new red sandstone, so that I feel 

 as if the discovery of this plant in the valley of the Connecticut, 

 ought to strengthen the opinion which I have for some time 

 maintained, that the sandstone of that valley belongs to the new 

 red sandstone of geologists. 



Dr. James Deane, of Greenfield, has recently presented me 

 with a few small fragments of a fossil plant, found in the shale 

 of the same formation, in Montague, in Massachusetts, where a 

 few years since an effort was made to discover coal. These are 

 shown of the natural size on Plate XII, figs, 3, 4, and 5. Though 

 imperfect, I can hardly doubt but they should be referred to the 

 Voltzia ; another characteristic plant of the new red sandstone. 



Description of the Oxide of Tin found at the Tourmaline 

 Locality, Chesterfield, Mass. By J. E. Teschemacher, 

 of Boston. 



In the edition of Mohs' Mineralogy by Haidinger, it is stated, 

 that small groups of black twin crystals of oxide of tin had been 

 discovered in the Albite rock of Chesterfield, Mass. ; and in Dana's 

 Mineralogy it is stated, that a few crystals of tin ore had been 

 found there : but as no particular description has been given, and 

 as most mineralogists had been unsuccessful in their search after 

 this interesting mineral, many suspected that some error existed, 

 and that tin had not been found in that locality. 



Having been fortunate enough to find a few very perfect crys- 

 tals, in specimens from this place, I presume it will be interesting 

 to ofter a description of their physical qualities, by which all doubt 

 on this subject will be set at rest. But I will first read an extract 



