12 BULLETIN 66, UNITED STATES NATIONAL MUSEUM. 



in Formicoidea ; Eumenidas, Vespidae, and Masaridse in the Ves- 

 poidea; Sphecidae, Stizidse, and Bembecidse in the Sphecoidea; and 

 Anthophoridse, Panurgidas, Andrenida?, and Prosopidae in the Apoidea. 

 These families include social ants, social wasps, solitary wasps, 

 digger bees, gall-dwelling bees, and stem-dwelling bees. 



The Hymenoptera campaign should consist of several features: 1. 

 A systematic search of all flowers blooming in the locality studied 

 at all times of the year. 2. A careful record of the host plant, time 

 of appearance and disappearance of each species of bee and wasp. 3. 

 A systematic search for the dwellings of the bees and wasps and 

 sweeping in their vicinity. 4. A study of the interior conditions of 

 the dwellings of each species. 5. Studies of ants' nests. 



On the other hand, a systematic study of the Strepsiptera must also 

 yield to the world — 



1. A fuller knowledge of the biology of the host insects. 



2. An increase in the knowledge of inter- relationships of insects. 



3. An addition to the recorded knowledge of the other parasites of 

 the same hosts (as, for instance, Rhipiphoridse, Meloidse, Braulidae, 

 etc.) . 



The collection of males on the wing would seem to be attended by 

 considerable difficulties, because of the rapidity of flight and the 

 minute size of the insects. The best results must come from breed- 

 ing the hosts. In the study of Acroscliismus pallidus the writer found 

 a very convenient arrangement in the shape of an ordinary broad 

 lamp chimney. A pasteboard box was arranged as a support in order 

 to keep the globe in one position and yet horizontal. The ends were 

 merely covered with cheese cloth. A wire screen divided the globe 

 into two compartments, in the upper of which were the wasps and 

 into the lower of which the parasites dropped when exhausted. One 

 end was closed by pasteboard with a hole cut in the middle, through 

 which with a dropper sugar or water could be admitted to a pill box 

 placed on the screening. The pasteboard end was covered with a 

 cheese cloth also. It is not advisable to crowd a cage with wasps. 

 They can be admitted through the same hole intended for the food 

 passing. The parasites can be removed with a camel's-hair brush, 

 but the student must take great precautions, as they are so quick of 

 flight. 



One of the desiderata in working with Strepsiptera is to get the 

 triungulinids as well as the adult male and female; hence arrange- 

 ments must be perfected by the student to keep the hosts alive until 

 time for the triungulinids to emerge. 



In the preservation of specimens the writer finds it very inadvisable 

 to mount dry, as the specimens invariably shrivel up, and also because 

 so many of the best characters of the Strepsiptera are microscopic. 



