68 



BIOLOGICAL LECTURES. 



swamp. The case is an interesting example of how instructive 

 the study of the strata themselves may become from the 

 strictly biological point of view. 



So far we have been dealing with an aspect of our subject 

 which is geological rather than biological, but which yet repre- 

 sents the indispensable preliminaries of any truly scientific 

 study of palaeontology. Coming now to the aspects which 

 deal more directly with the latter, we must obviously begin 

 with the subject of collecting. There is all the difference in 

 the world between good and bad collecting, and the work of 



FIG. 3. Sandstones formed in old stream-channels; White River Bad Lands. 



the careless or incompetent collector is so mischievous, so exas- 

 perating, so destructive of valuable material, that one is often 

 tempted to wish that the work might be prohibited to all save 

 thoroughly trained and careful men. Of course, the first step 

 in collecting is to find something. I find the impression very 

 widely spread that the collector goes out into the bad lands 

 and begins to dig at random, until he happens upon a bone. If 

 he were to undertake his work in such a foolish way, experience 

 would soon teach him that he might employ his time more 

 profitably in any other possible calling. The specimens must 

 be found by surface indications. In order to do this, the 



