INTRODUCTION. 



The material presented in this bulletin consists of a number of lec- 

 tures or talks delivered at the University of Montana Biological Station 

 in the summer of 1902, by the station staff. Not all the lectures are 

 given. Many of the illustrations, such as photographs, charts, and draw- 

 ings, have of necessity been omitted, owing to the expense of reproduc- 

 tion. The lectures on protective resemblance and mimicry were illus- 

 trated by numerous colored drawings and charts, the work of Mrs. Maurice 

 Ricker. But few of these can be reproduced, and they only in black and 

 white. While the absence of numerous illustrations is to be regretted, it is 

 thought the material presented will be of sufficient aid to warrant publica- 

 tion. 



The lectures are given for a double purpose. 



1. They should be of great service to teachers of the state in nature- 

 study work. Several are prepared expressly for this purpose. Some of 

 those treating of particular features of the locality may by slight modifica- 

 tion be made to apply to other localities. There has been an urgent 

 demand for just such information as is here presented, and the publica- 

 tion of the lectures will answer many inquiries that have been received. 



2. They will put before the people of the state some of the results 

 of original work carried on at the station. This is all the more desirable 

 since nearly all the observations in a new locality must for a titne be new, 

 and hence deeply interesting. It is hoped they will show in part the 

 wide field open for research, and encourage the attendance of many who 

 are seeking such a place for study. 



Since the lectures or talks were delivered to audiences of whom many 

 were unacquainted with the subject and with technical terms the simplest 

 language has been used, thereby making them of greatest service. 



M. J. E. 

 Missoula, Mont., April 27, 1903. 



