55 APPARATUS NEEDED. 



It is very desirable that the laboratory be provided with an 

 Abbe camera lucida and some high power objectives; e. g., a 1-10 or 

 1-12 oil immersion. A substage condenser is very desirable when 

 such high magnification is to be used. 



It is necessary that each student be provided with a good 

 section knife or razor. One of the latter ground flat on one side 

 and concave on the other is preferable. The edge should be kept 

 very sharp and keen, otherwise the sections will be uneven and torn. 

 A suitable hone and strap are needed in the laboratory for keeping 

 the edge in order. Unless the students can be carefully taught 

 how to sharpen a knife, it should be taken to some one familiar with 

 honing razors. For cutting sections of lignified or cutinized ma- 

 terial, an old razor should be used, as the edge will almost invari- 

 ably be injured. Various pieces of apparatus not mentioned will 

 be found very useful and materially aid in careful and thorough 

 work, yet much can be accomplished without any very extensive 

 expenditure of money for equipments. 



