Transactions of the Oeological Society of Pennsylvania. 351 



ferous red earth from two to three and a half feet wide, and bounded 

 also by talcose slate. The auriferous quartz vein has been exposed 

 to view for six hundred and twenty seven feet ^vith a width of thirty 

 inches, and it would appear that this is only the beginning. By a 

 rough process of washing, amalgamation and evaporation of the mer- 

 cury, three and a half grains of gold were obtained from four pounds 

 of the ore taken indiscriminately from all parts of the vein, and in 

 another experiment five grains of gold were produced from four 

 pounds of pure milk-white quartz, which had no appearance or in- 

 dication of containing any metal at all. 



Messrs. Del Rio and Millington think that each pound of the ore 

 may be made to yield one grain of gold or five pennyweights to the 

 one hundred pounds of ore ; this would much more than pay the 

 expense, which cannot exceed one dollar on one hundred pounds of 

 the cmde material. It appears that by heating the quartz red hot 

 and throwing it into cold water, eight grains of gold were obtained 

 from five pounds of ore. In the opinion of Mr. Dickson, the Rap- 

 pahannock mines perfectly resemble all the others in Virginia. On 

 the whole the gold region of the United States is very extensive, rich 

 and promising, and there is every adventitious advantage of fuel, food, 

 climate, cultivation and security. 



We have seen a decisive experiment of this kind made upon white 

 quartz from Virginia which yielded a considerable quantity of gold 

 by simple pounding and w'ashing without amalgamation. — Ed. 



3. New Trilohite, ^c. 



Dr. Jacob Green whose excellent monograph on the trilobites of 

 this country, illustrated by beautiful plaster models is well known, 

 has described in the Geological Transactions of Philadelphia, a new 

 trilohite found by Dr. C. T. Jackson in Nova Scotia, in magnetic 

 iron ore which is beautifully impressed by various organic bodies, 

 among which the present trilohite, called by Dr. Green Asaphus 

 crypturus is conspicuous. For the description and drawing we must 

 refer to the Transactions. 



Dr. Green has also given an account of the chemical examination 

 of a sulphated ferruginous earth from Kent county, Delaware, with a 

 view to ascertain its.commercial value. 



4. Fossil Zoology and Comparative Anatomy. 



Dr. Harlan has comnnmicated a good paper on the structure of 

 the teeth in the Edentata, fossil and recent; and this is followed by a 



