Annual Meeting.] 226 [May 6, 



Eeport of Alpheus Hyatt, Curator. 



The Curator has for some years past recognized the need of 

 making a collection which should serve as an explanatory intro- 

 duction to the Museum of the Society. This collection should 

 stand in the vestibule, where there is ample room for its accommo- 

 dation, and where it would necessarily first demand the attention 

 of a visitor. 



It should consist of three parts or sections, first Statical Geog- 

 nosy or Physiognosy ; second, Dynamical Geology ; third, Dynam- 

 ical Biology. The examples should be well selected, comparatively 

 few in number, and so arranged, that a visitor would be able to 

 grasp within a limited time the leading ideas which have governed 

 the arrangement of the whole. In other words, it should be a con- 

 centrated and illustrated history of the relations of the earth and 

 its products. The plan is perfectly feasible and some of the ma- 

 terials are already at hand by which it can be effectively begun. 



The first section should contain the models of the earth and 

 sun which we already have, and specimens exhibiting the compo- 

 sition of the earth, its mineral, vegetable and animal constituents, 

 and their importance and relations when considered as substances 

 in a state of rest. This first section, therefore, as suggested by 

 Prof. W. O. Crosby, would be most appropriately termed a statical 

 collection in contrast with the succeeding dynamical collections. 



The second section, Dynamical Geology, needs hardly any ex- 

 planation. It should show the results of the action of the various 

 forces, which have moulded the continents and formed the basins 

 of the oceanic areas. The first series of examples would exhibit 

 the action of subterranean forces, or what should be termed the fun- 

 damental causes of modification, which have upheaved mountains 

 and depressed the complementary parts of adjoining areas, the re- 

 sults of earthquakes and land slides, faults, volcanoes and so on. 



The second series of examples should show the action of the 

 more superficial or secondary agencies, such as the effects of denu- 

 dation which have destroyed the land by sweeping off of the sur- 

 face, the carving out of river channels, and the transportation of 

 sediments to the sea, the formation of rock masses by the accu- 

 mulation of this debris in the sea, the building up of land by an- 



