LABORATORY WORK 



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Equipment. A well-lighted laboratory provided with tables is 

 almost necessary, but the teacher may find it possible, with much 

 additional work and less satisfactory results, to conduct the exercises 

 at the students' ordinary desks. The apparatus required will depend 

 upon the exercises selected. In any case there will be needed at 

 least one large aquarium. For this purpose battery jars twelve inches 

 in diameter will be found serviceable. For keeping living insects, 

 cages made of wire netting, placed over food plants growing in broad 

 " seed-pans," are recommended. An ingenious teacher will be able 

 to make many cheap substitutions for some of the apparatus 

 specified. Thus in place of " Stencler dishes " tumblers may be 

 used. 



Laboratory book's. The drawings should be made on a good 



