1 879-i88o.] 409 



limestone. There we re also exhibited the microscopic shells of 

 Foraminifera, which are now forming vast beds of limestone, 

 hardly distinguishable from chalk, at the bottom of the Atlantic 

 and Pacific Oceans. Some of the latter, from the Challenger Ex- 

 pedition, were exhibited by Mr. Charles Elcock. Some remark- 

 able fine specimens of stalactite and stalagmite, from limestone 

 caverns were also shown, as well as petrifactions of animals, birds 

 nests, and other objects, formed by the deposit of carbonate of 

 lime in springs. As usual, a number of the members had their 

 microscopes at work, and exhibited various microscopic specialties. 

 The President, Mr. W. Gray, M.R.I.A., showed several objects 

 multiplied by being seen through the eye of an insect, in which, 

 within a diameter not much larger than a small needle, were seen 

 upwards of four hundred separate representations of the words, God, 

 man, art, &c. Mr. James Wright exhibited in an interesting 

 manner the circulation of sap through the Valisneria, one of our 

 exotic water-plants. The Rev. Canon Macllwaine, D.D., 

 M.R.I.A., exhibited some slides showing the polarisation of light. 

 Mr. Joseph Wright, F.G.S., showed some recently-discovered 

 sponge spicules from the Carboniferous rocks of Sligo, being the 

 first indication yet found of their existence in the Irish carbon- 

 iferous formation. Mr. Firth, in conjunction with Mr. I. W. Ward, 

 exhibited some beautifully- mounted diatons and sections of lime- 

 stone, and Mr. John Pim and Mr. John Browne, M.R.I.A., also ex- 

 hibited a number of interesting microscopic objects. In addition 

 to his microscope, the President (Mr. W. Gray) exhibited a varied 

 collection of interesting objects. Amongst these was a case of very 

 fine fossil fishes from the Cretaceous rocks of Mount Lebanon, and 

 a fine collection of stone implements from America. He also 

 shewed some bronze and stone weapons recently dredged from 

 the River Bann near Toomebridge. Some Japanese magic mirrors 

 also exhibited by him attracted considerable attention. The Rev. 

 Canon Macllwaine exhibited a splendid stone war-club, or hatchet, 



