Mr William Stevenson on the Origin of Granite. 165 



IV. On the Homology of the Vertebrate Cranium. By Professor 

 Macdonald, St Andrews. 



Wednesday, 27th April 1864. — William Turner, Esq., M.B., 

 President, in the Chair. 



David Young, Esq., Medical Missionary Dispensary, Cowgate, was 

 balloted for, and elected a non-resident member of the Society. 



The Report of the Treasurer, Mr G. Logan, W.S., was read and 

 approved. 



The usual Committees were appointed, for prosecuting special in- 

 vestigations during the summer recess. 



The following Donations were laid on the table, and thanks voted to 

 the Donors : — 



1. Proceedings of the Academy of Natural Sciences of Philadelphia. 

 1863. — From the Academy. 2. Proceedings of the Literary and Phi- 

 losophical Society of Liverpool, No. 47, 1862-63. — From the Society. 



3. Proceedings of the Royal Society, Nos. 57-61. — From the Society. 



4. Canadian Journal of Industry, Science, and Art. New Series. Nos. 

 48, 49. Nov. 1863, Jan. 1864. — From the Canadian Institute. 5. 

 Jahrbuch der Kaiserlich — Koniglichen Geologishen Reichsanstalt, 1863. 

 XIII. Band, Nro. 3, Juli, August, September. — From the I. R. Geolo- 

 gical Institute of Austria. 6. Dublin Medical Press. Second Series. 

 Vol. VIII. No. 199. — From the Publisher. 7- Journal of the Proceed- 

 ings of the Linnean Society. A complete series from March 1856 to 

 October 1863.— From the Society. 



The following Communications were read : — 



I. On the Origin of Granite. By Wm. Stevenson, Esq., Dunse. Com- 

 municated by George Logan, Esq., W.S. 



The object of this paper is not to discuss the various 

 opinions which have been held relative to the origin of 

 granite, — opinions with which the Members of this Society 

 must all be familiar, but simply to lay down a proposition 

 embodying the author's views on the subject, — following this 

 up by references to the phenomena exhibited in certain loca- 

 lities, so that all who feel interested may go to nature, 

 examine and judge for themselves. 



Proposition. — Granite is the result of the fusion (total or 

 partial), by means of molten felspar, of rocks adjacent 

 to the place of eruption. 



It may be of any geological age, but is in general found 



