BOHART: STREPSIPTERA i 567 



described by Peter Rossi in 1793 and twenty years later, in 1813, Kirby erected 

 the order Strepsiptera. This did not find favor witli the majority of taxonomists, 

 and the group was placed generally in the Coleoptera or less frequently in the 

 Diptera, Neuroptera, or Hymenoptera. 



In the following fifty-five years only 3 more genera were described but 

 our knowledge was increased to a greater extent along other lines. The only 

 fossil strepsipteran now known, Mengea tertiaria Grote, was reported by Menge 

 in 1866 in Baltic amber. This indicated that the order had not changed greatly 

 since Tertiary times. In 1893 Nassonow gave the first account of internal anat- 

 omy and his work is still the best available on the subject. Another step forward 

 was a paper by Perkins in 1905, which described the life histories of several 

 parasites of leafhoppers and suggested their possible importance in biological 

 control. 



The stage was set for an expansion of the Strepsiptera along systematic lines, 

 and from 1909 to 1918 W. D. Pierce dominated this field. Holding stubbornly 

 to a theory of host-parasite specificity, Pierce raised the number of described 

 species by 1918 to a total of 166, which he distributed among 5 superfamilies, 

 11 families, 8 subfamilies, 5 tribes, and 49 genera. Fortunately, later workers 

 have been able to reduce this top-heavy structure to 6 families and 16 genera, to 

 which 7 more have been added. The chief value of Pierce's papers was that 

 they assembled for the first time all the scattered references to the order so that 

 workers in various parts of the world could proceed on a common basis. 



At this time (1918) it was thought that all female Strepsiptera were endo- 

 parasitic for life, beginning with the second larval stage. This idea was blasted 

 by Peyerimhoff, who described the free-living female of Eoxenos in 1919. An- 

 other major contribution was that of Salt (1927) dealing extensively with the 

 effects of stylopization. He pointed out that in the Hymenoptera those hosts 

 which had a fixed amount of larval food, such as the solitary Vespidae, fre- 

 quently assumed the characters of intersexes, whereas the hosts continually fed 

 as larvae, such as the social Vespidae, exhibited no such external differences. 

 The work of Peyerimhoff bore fruit after fifteen years when, in 1934, Parker 

 and Smith associated the female Eoxenos with a mengeid male and established 

 the female of the Mengeidae for the first time. All that remained to complete 

 the skeleton framework of the picture in this family was to find the host. This 

 turned out to be a thysanuran, as reported by Carpentier in 1939. In the same 

 year Ogloblin published the first evidence of females in the family Myrmeco- 

 lacidae. His startling finds indicate that the males parasitize ants and the 

 females mature in various types of Orthoptera. Also in 1939, Lindberg, working 

 with Elenchus parasitic on a fulgorid, gave the first complete record of the re- 

 lationship between a strepsipteran and its host. 



The first major review of the order since that of Pierce in 1918 was attempted 

 by Bohart (1941) who revised the world genera and the species of North Amer- 

 ica. It was here that many of the superfiuous categories of Pierce were synony- 

 mized. Bohart followed this with the first comprehensive paper on the leafhopper 

 parasite family Halictophagiclae in 1943. Also in 1943, Hofeneder and Fulmek 

 published a complete cross-reference catalogue to the parasites and their hosts, 

 and Silvestri gave a comprehensive treatment of the biologies of 6 Italian species 

 of Mengenilla. 



