1 8 INTRODUCTION". 



anatomy the number of drawings has been mostly left 

 to the discretion of the student. 



In minute anatomy the points at which drawings 

 may most profitably be made are carefully noted. In 

 many instances, however, it is so difficult to secure a 

 wholly satisfactory section to show certain structures, 

 that they should be drawn whenever found in good 

 condition, without regard to the directions. 



Drawings in minute anatomy may be either free- 

 hand or with camera lucida. In free-hand drawing the 

 student is especially cautioned against making them 

 too small, which is a very common fault. In the out- 

 lines for work it is expected that accurate drawings be 

 made unless a diagram or diagrammatic drawing is 

 called for. A diagram (fig. 11) shows only a single 

 special feature, or at most two or three, while a dia- 

 grammatic drawing (fig. 8 or 10) shows all the chief 

 features, but does not take note of smaller matters, 

 such (e. g.) as distinguish the several cells of the same 

 tissue. When an accurate drawing is to be made, each 

 individual cell should be drawn as carefully as if it 

 were the whole object. When an accurate drawing 

 includes considerable tissue, time may be saved by 

 indicating the boundaries between the tissues by dot- 

 ted outlines, and only cells enough filled in to show 

 the character of the tissues. 



In order to draw to scale with the microscope it is 

 necessary to use a camera lucida. The magnification 

 is thus determined : place a micrometer on the stage 

 of the instrument in the same position as an object, 

 adjust the instrument as for drawing, and laying a 

 common rule on the drawing paper read off the dis- 



