i68 



PRACTICAL MICROSCOPY. 



removal of loose matter, torn and unrequired portions of 

 the insect anatomy, and also for the arrangement of the 

 dissected portions. 



The knives used in dissecting should be of good steel, 

 and kept in order by the occasional application of a 

 Washita oilstone. Some of the most useful forms are 

 shown in Fig. 153 two or three will perhaps be selected ; 

 the author prefers the forms shown at a, b, d, f and h. 



Nearly every microscopist prefers to work his own way, 

 and with his own choice of instruments. The spear-head 

 needles sold by Mr. Ward of Manchester will be found 

 exceedingly useful. 



Three kinds of scissors are generally required by the dis- 

 sector, the curved, Fig. 1 54, elbow, Fig. 155, and plain, Fig. 

 156. They must be well made, and kept carefully cleaned 

 and free from rust. The application of mercury ointment 



