504 



INJURIOUS AXD BENEFICIAL INSECTS OF CALIFORNIA. 



Ijzoc; 



.-iaphit 

 i 

 I 



oi iginal shapes perfectly, but are not suitable for microscopic study for 

 several months. By far the most satisfactory method of mounting 

 scale insects is to first boil them in potassium 

 hydroxide (KOH) or sodium hydroxide (NaOH) ; 

 thoroughly wash them in water; dehydrate by 

 carrying through solutions of 30 per cent, 78 per 

 cent and 95 per cent or absolute alcohol ; clear in 

 xylol, cedar oil or clove oil and mount directly into 

 balsam. 



An excellent method of mounting the others 

 listed above is as follows : kill by pouring over them 

 boiling 95 per cent or absolute alcohol ; clear in 

 xylol, cedar oil or clove oil, and mount directly into 

 balsam. Glass slides and cover glasses are neces- 

 sary for such mounts. 



PRESERVING LARVAE 



Caterpillars are very often preserved by the in- 

 flating method, which consists in removing the 

 viscera, inflating the bodies and drying them oyer 

 an oven until they become rigid. The original 

 shape, color and much of the vestiture are thus 

 retained in almost perfect condition. 



Caterpillars and the larva? of other insects are 

 also excellently preserved by first boiling them in 

 water and placing them directly in a permanent 

 solution prepared as follows : 



Alcohol (95 per cent) 15 c.c. 



Formalin (40 per cent") 15 c.c. 



Water (distilled) 120 c.c. 



Fig. 503. — Wooden 

 box for microscopic 

 slides. Such a box 

 holds 25 thick and 50" 

 thin slides. Reduced 

 one half. (Original) 



SENDING INSECTS BY MAIL 



Insects sent through the mail for determination 

 should be well packed in a small box, so that they 

 can not be crushed in transit, and should be securely 

 packed in cotton or bits of paper, so they can not 

 rattle around and lose all or most of the appendages. Alcoholic speci- 

 mens may be sent in regular mailing tubes without danger of breaking. 

 All specimens should be sent in large numbers and accompanied with 

 the name of the food plant, locality, date of collection and the name 

 of the collector and sender. 



