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There is no described species which varies so much in length 

 of tegmina as ours does. In Redtenbacher's Monograph of the 

 ConocephaHdae, the long-winged species of Xiphidium are sep- 

 arated specifically from the short-winged species. It seenis prob- 

 able that m'any of the species described as short-winged, may 

 be but short-winged forms of the long-winged species, or vice 

 versa. 



In the United States five species of Xiphidium have been ob- 

 served 'to have dimorphism in the wings. 



X. cnsifcrum Scudder, Usually short-winged; "long-winged 

 forms are found occasionally"" 



X. iiigropleurum Bruner, "Tegmina are usually abbreviated." 

 "An occasional specimen is to be found in which the 

 wings are fully developed."" 



X. strictuni Scudder, "Dimorphic, the long-winged forms, 

 however, being very scarce."** 



X. attoiuaUim Scudder, Dimorphic, but only short-winged 

 forms mentioned for Minnesota." Both forms in Indi- 

 ana, about equally abundant in the northern part, only 

 the short-winged form in the southern part of State.** 



X. saltans Scudder, Usually short-winged. "A long-winged 

 pair August 9, 1903."*** 



I have found no mention of intermediate forms in connection 

 with the dimorphism of these species. 



Blatchley t says of the Genus Xiphidium, "Variations in length 

 of wings seem to be abrupt with no intervening forms. There 

 are long-winged iand short-winged forms of the same species, 

 but none with the wings of medium length. Four of our eight 

 species are thus dimorphic as regards the length of the wings, 

 the short-winged individuals, as far as my observation goes, far 

 outnumbering those with the wings fully developed." 



From my table of measurements it will 'be seen that there is 

 a small proportion of individuals of X. varipennc which have 

 wings of medium lengths. I am of the opinion that interme- 

 diate forms may yet be found in other species; and further, 

 that more of the species may be found to be dimorphic as re- 

 gards wings. 



Our species was referred to A^ fitscum Fab. by Brunner, "Or- 

 thoptera of the Sandwich Islands," P. Z. S., London, p. 894, 

 1895. T he same name is used by Perkins, Fauna Havvaiiensis] 



** ^}^^^?^' ^"^'- ^'^' *^*""- ^"- E^P- station, pp. :«l, 2, 3, 1897 

 - Walker'&au.''E,ft"xxlvK; f^^ ""''■ ^^^°"'-^'^^' ^P" ^^^' ^^'' 1902. 

 t Orthoptera of Indiana, 27th An. Rep. Dep. of Geol. and Nat. Resources, p. 371, 1902. 



