1 68 BIOLOGICAL LECTURES. 



you can find any important monograph which certainly or 

 probably deals with your subject, consult that, of course. 

 Finally, if your question is one medical men are likely to have 

 discussed, look through the Reports of Virchow-Hirsch and 

 Schmidt's JaJirbucJicr, and also through the various medical 

 journals of the Ccntralblatt type (see p. i66, above). 



I have dealt with a difficult and, I fear, very dry subject, 

 and can only hope that some of my suggestions will prove 

 helpful. It is profitable to consider sometimes the ways and 

 means of science as well as her results, for the investigator's 

 success depends upon his mastery over both means and results, 

 and this double mastery can be had only by those who also 

 command the complex bibliographical resources of biology. I 

 hope that our review of these resources will encourage some of 

 you to enter, others to advance along the paths of research ; 

 and I trust that you all, when you leave the laboratory, will 

 carry with you a deeper and loftier enthusiasm for original 

 research, which is at once the chief duty and the chief privi- 

 lege of the biologist. 



Revised at Boston, Decejiiber, 1895. 



