354 



ELEMENTARY ENTOMOLOGY 



FIG. 491. Method of mounting inflated larvae 

 (After Washburn) 



The rolling is then continued until the entire contents of the body 

 have been forced out through the posterior end. A straw or a 

 glass tube which has been drawn out to a fine point is next in- 

 serted through the open- 

 ing. This may in turn be 

 attached to a rubber tube 

 and bulb, or the larva 

 may be inflated by blow- 

 ing gently through the 

 tube. In order to keep 

 the specimen on the end 

 of the tube, it should be 

 allowed to dry for a few 

 minutes. To thoroughly dry the skin it is kept distended inside a 

 glass lamp chimney, which rests in a pan of sand over a gas or 

 alcohol flame, as shown in Fig. 490. When the skin is thor- 

 oughly dried, it is removed from the glass tube and may then be 

 mounted on an elbow pin by bending the point of the elbow into 

 a loop, which is dipped into glue and inserted into the opening in 

 the abdomen. Another method is shown in Fig. 491. 



Dissecting instruments. The number of 

 different instruments required for the study of 

 the anatomy of insects is not great. However, 

 owing to the small size of the specimens 

 studied, the instruments should be of the very 

 best material. 



Forceps. Forceps should be of two kinds, 

 curved-pointed and straight-pointed (Fig. 492). 

 Both pairs should have very fine points which 

 are slightly roughened. 



Scissors. Curved scissors will be found very 

 useful in carrying on minute dissecting, work, 

 the difficulty being to secure a pair that will 

 cut entirely to the point. In using the fine- 

 pointed scissors, care must be exercised not 

 to strain them by cutting too thick objects. 



Scalpels. These are of less importance in 

 entomological work than in most other forms straight-pointed 



