VI 



Page. 



General Meeting, February 20, 1878 309 



Mr. M. E. Wadsworth. Notes on the Petrography of Quincy and Rock- 



port 309 



Prof. H. Weyenbergh. Two New Species of Pachylus from the Argen- 

 tine Republic 316 



Section of Entomology, February 27, 1878 320 



Mr. Edward Burgess. Two interesting American Diptera (Plate 9, 



figs. 1, 2) 320 



General Meeting, March 6, 1878 324 



Prof. W. H. Niles. Zones of different Physical Features upon Mountain 



Slopes 324 



General Meeting, March 20, 1878 330 



Prof. W. H. Niles. Relative Agency of Glaciers and Sub-Glacial 



Streams in the Erosion of Valleys 330 



Section of Entomology, March 27, 1878 336 



Mr. S. H. Scudder. Note on Dimorphism in Acrydians . . . 336 



General Meeting, April 3, 1878 337 



Prof. B. G. Wilder. Aereal Respiration in the Mud Fish . . .337 



An apparatus to illustrate the action of the Diaphi-agm in Respiration 337 



General Meeting, April 17, 1878 338 



Mr. Richard Rathbun. Sketch of the Life and Scientific Work of Pro- 

 fessor Charles Frederic Hartt . . . . . . . .338 



Mr. P. R. Uhler. A list of the Hemiptera Heteroptera in the Collection 



of the late T. W. Harris , . . 365 



