14 Annals Entomological Society of America [Vol. VI, 



Several times the writer noted roaches in the cages, and the 

 crops of the dissected roaches, as well as the appearance of the 

 adults in the cages, showed the "why" of their presence. 



2. The Care of Adults. 



A. At the Field Laboratory: It is necessary each morning 

 to remove the jars containing pupae from the screen cages. It 

 will be found that no few adults remain on the sides of the glass 

 jars. These are readily transferred into the screen cage by 

 holding the cage in direct sunlight and tapping the jar briskly 

 with the hand. When the jars are removed, the holes in the 

 cage which served to receive them, must be plugged snugly with 

 cotton waste to prevent the escape of any adults. The cage 

 must now be placed in a sheltered corner and left for several 

 hours, or until the chitinous portions of the exoskeleton have 

 hardened and the wings stiffened. Precaution must be taken 

 against the invasions by ants and roaches. Avoid rapid evap- 

 oration and direct sunlight. 



B. Tra7isporting Adults to Stations: Colored adults should 

 not be carried to several localities, the danger of the accidental 

 escape of a colored one en route being too great. Adults, 

 unstained, are best transported in the morning or evening, and 

 each cage should be securely closed and partly encased in a 

 damp cloth. The uncovered side should be underneath. An 

 oil cloth cover is neccessary during showers. In two instances, 

 when no covers were used, and the cages carried through light 

 showers, all the adults were killed. Protection from wind was 

 found necessary. Air currents cause rapid evaporation which 

 the mosquitos cannot withstand. 



3. Coloring of the Adults. 



A. Dyes Used: Aqueous solution of eosin, fuchsin, gen- 

 tian-violet, bismarck-braun, methylene-blue and orange-g, were 

 used with good success, the proportions of dry stain to water 

 being about one gram to fifty cc. It is best to make small 

 quantities at a time as stock solutions may deteriorate. All 

 stains should be kept locked up. Likewise staining operations 

 should be known only to a few. Curiosity too frequently gives 

 birth to trouble. 



It may not be amiss to state under this section two other 

 "markers" which may be used effectively with larger diptera. 

 In our work they were not as serviceable as the dyes. The 



