PRINCIPLES OF ANIMAL BIOLOGY 7 



The student should note that the oculars are marked to denote their 

 magnification, thus, 8x and 4x, while the objectives are marked in terms 

 of their focal length, thus, 4 mm. and 16 mm. These terms should always 

 be used in designating the oculars and objectives rather than the ex- 

 pressions high power and low power, or large and small. 



5. Other objects will be furnished for examination. 



Note to the Student. The work of this laboratory period constitutes 

 report number 1. Place all the notes and the plate (see that each sheet 

 of your work has your name on it) in an envelope, fill in the blanks giving 

 as the subject of this report "The Relation of Object and Image," and 

 put the envelope in the place indicated by the instructor. Put every- 

 thing away in good order. Put waste paper in the waste basket; push 

 the chair or stool under the table; leave the table in as good condition 

 as you would like to find it. Take this book of laboratory directions 

 home with you and study carefully the general laboratory regulations, 

 the statements concerning the laboratory records, and the use of the 

 microscope. 



Be ready for a quiz at any time on the work completed. 



