GLASGOW SOCIETY OF FIELD NATURALISTS. 143 



Mr. Robert Walker, 6 Nelson Terrace, Hillliead, was elected a 

 member of the Society. 



SPECIMENS EXHIBITED. 



By Mr. E-. H. Paterson. — A collection of licbens : Scyphophorus 

 alicornis, S. hellidiflora, S. deformis, S. Jimbriatus, S. coccifera, S. 

 gracilis, Genomyce pigridate. Also the fungus Polyporus gigan- 

 teus. The last from the Cameroons, Africa. 



PAPER READ. 



Mr. J. Galbraith, M.A., read a paper on "Volcanism," or, as 

 he said he would prefer to have it called, " Vulcanology " — the 

 science which treats of volcanoes and earthquakes, and the causes 

 which produce them. After i-eviewing the various theories of Sir 

 Humphry Davy, Mallet, Hopkins, and others, he went on to pro- 

 pound a theory which might, to some extent at least, harmonize 

 the whole of them. He afterwards gave an account of the various 

 manners in which changes of igneous origin are produced on the 

 earth's crust, of the best known volcanic eruptions which had 

 occurred, and of the active volcanoes which are best known to 

 science. 



11th January, 1876. 

 Mr. Richard M'Kay, Vice-President, in the chair. 



PAPERS READ. 



Mr. James Allan read a paper on the " Migration of Birds." 

 He began by noticing the wonder excited by the disappearance of 

 birds, and the legends connected therewith, and the omens drawn 

 from their flight by the ancients. Partial migration occurred in 

 the case of the lapwing, which leaves the bare moorlands in 

 winter and proceeds to the sheltered valleys. He laid before the 

 meeting the following series of tables, in which the arrivals and 

 departures of various birds were registered, extending over a series 

 of years. He found that the corncrake seemed to be the most 

 regular in its return, and the swallow the most irregular. But 

 taking the average of any one year, it cannot be said that in such 

 a season all birds appeared later or earlier. The chiff-chaff is 



