120 The Ohio Naturalist. [Vol. VII, No. 6, 



together over the funnel. The insects falHng on the smooth 

 surface tumble down into the bottle. Damp wood, leaves, etc., 

 should be placed in the bottle for the insects to crawl over. 



Collecting Ix Fixatives. — For fixing the insects in the 

 field the collector should be provided with a large number of 

 small round bottomed vials filled with the fixative. Two or 

 three fine camel's hair brushes, a large square of white oil cloth 

 and a chizel or pick for dislodging bark or decaying wood. 



Pieces of bark, wood, etc., may be pounded together over the 

 cloth on which the insects wih fall. The tip of the brush is then 

 moistened with the fixative and quickly placed over the insect. 

 They should be held under the brush until stupified and then 

 placed in the fixing agent; the latter process being easily accom- 

 plished if the brush is sufficiently moistened. The matter of 

 proper fixation is very important. Almost all Thysanura are 

 impervious to water. Smynthuridae will float about for days or 

 even weeks on 75% alcohol, and the addition of a little glycerine 

 to 85% alcohol will prevent them from sinking. While 75% 

 alcohol will kill the specimens it fails to fix the tissues and they 

 soon shrivel and become useless. In working with the Thysa- 

 nura I have found the following reagents to be the most useful 

 both for form and general appearance, as well as internal 

 anatomy. 



Glacial Acetic Alcohol: 



Glacial Acetic Acid 1 part 



Absolute Alcohol 1 part 



Corossive Sublimate Saturation. 



For field collecting this is one of the best formulas I have 

 used. Specimens are fixed within a few seconds, btit may be 

 left in the reagent for several hours without detriment. They 

 mav be preserved indefinitely in 85% alcohol, or gradually 

 transferred to pure gvlcerine as follows: Place the specimens in 

 a stentor dish, and add glycerine from one side. After a con- 

 siderable amount of glycerine has been diffused through the 

 reagent the cover should be removed from the dish and the 

 glacial acetic and the alcohol allowed to evaporate. 



Acetic-Glycerine Fixing Agent: 



Glacial Acetic Acid 10 parts 



Glycerine 1 to 4 jiarts 



Corrosive Sublimate Saturation. 



Possibly better results may be obtained, es])ecially as to pre- 

 serving the color by the use of this reagent. Specimens will 

 be ])roperlv fixed in a few minutes, but may be left in the solution 

 for some time. On exposure to the air evaporation of the glacial 

 acetic takes place leaving only the glycerine. After this has 



