X Introduction 



The desk illustrated in the figure is twenty-seven Inches 

 high, and is made of pine boards, one inch thick ; the top 

 board is eighteen inches wide by thirty-two inches long. 



Whenever possible, each pupil should be provided with 

 a compound microscope, magnifying to about five hundred 

 diameters. There are, of course, many forms of micro- 

 scopes to choose from. In selecting them, the aim must 

 generally be to get the best instrument for the least money. 

 In my own laboratory I have used with satisfaction the 

 Leitz Stand No. 2, with objectives 3 and 7 and eye-pieces 

 I and 3, an outfit costing $17 when imported duty free. 

 The stand has no rack and pinion adjustment, but it 

 serves its purpose admirably. Similar simple forms of 

 American makers will probably prove equally satisfactory, 

 and there should be no difficulty in getting a microscope 

 suitable for work in elementary zoology at the price named. 



If the pupils have not before used the compound micro- 

 scope, a preliminary exercise should be given before the 

 work m zoology is taken up. An excellent guide to such 

 an exercise will be found in Dr. Charles H. Clark's " Prac- 

 tical Methods in Microscopy," in which there are also given 

 plain directions for preparing the few staining solutions 

 called for in this manual. 



A few glass slides, cover glasses, and two or three watch 

 glasses are necessary for each desk. A pair of small, 

 sharp-pointed scissors, forceps, and scalpel are also needed, 

 as well as a shallow tray or dish for the dissections that 

 are to be done under water. Shallow pans of granite-ware, 

 with sheet cork embedded on the bottom in plaster of Paris, 

 serve very well ; but the wax-lined dissecting trays now on 

 the market are the best of all. 



The teacher should be provided with the admirable 

 "Text-book of Zoology," by Parker and Haswell, the 



