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THE RESURRECTION OF THYANTA CALCEATA 

 SAY FROM SYNONYMY. 



By H. G. Barber, 

 Roselle Park, N. J. 



Professor E. B. Wilson, of Columbia University, in his researches 

 concerning the chromosomes of the germ cells of the species of 

 Thy ant a frecjuenting the eastern United States, came to the con- 

 clusion, from certain constant differences in the chromosomes, that 

 there were two distinct, but closely related species of this genus 

 which have hitherto been incorporated under Thyanta cnstator Fabr.^ 

 He turned all of his specimens over to me, including four specimens 

 of T. pcrditor Fabr. from Jamaica, W. E, with the request that I 

 work out the differentiation of the two species. At the same time 

 Professor Wilson pointed out to me certain differences in the shape 

 of the scutellum by which alone he was able to separate the two 

 species. 



Since receiving this material I have endeavored to gather speci- 



^ Professor Wilson states in his paper before the Seventh International 

 Congress in 1907, printed 1909, that he is readily able to differentiate the 

 two species from a microscopical examination of their germ cells, as T. calceafa 

 has 27 chromosomes in the male and 28 in the female, while T. cnstator has 

 16 chromosomes in both sexes. 



