AMERICAN LEPIDOPTERA. 203 



Fabricius describes his species as " subtus glaucis." This, Mr. Eil- 

 wards says, applies to the female umbrosa alone, of the males and fe- 

 males of the two species. If this were so, his determination njight be 

 admitted. But I have in my collection abundant material to prove con- 

 clusively, that either there is an error in his conception or restriction 

 of " glaucis," or, as might naturally be expected from the " great varia- 

 tion" (f^dw.) in I'ntei-rogafioiu's, the individuals which have come under 

 Ids observation, are differently shaded f\-o!n mine. I have now be- 

 fore me eighty-five ex lurv/f; specimens of !)itcrro(jationi^, and with no 

 other motive than the proper solution of the question at issue, I affirm, 

 that of the two species, i\\e^-iinhtis gfaucis" applies in a greater degree 

 to inft'rro(jnti(>nis than to umhio:<n. I have placed my specimens of 

 these two species before gentleiuen familiar with the colorational terms 

 employed in natural history, with the retjuest that they would indicate 

 which of the four (counting sexes) the best met their conception of 

 "glaucous," and in each instance, the females of interrof/dfionis were 

 unhesitatingly designated. I would premise, that at this remote day, 

 we should be at fault were we to decide upon the precise shade which 

 Fabricius intended by (jlaucis, of the many which its jjresent range 

 embraces, whether bluish-grey, grayish-blue, bluish, sea-green, dull 

 green, or a bloom like that upon a plum or cabbage-leaf Although 

 the shade by which 3Ir. E. prefers to define f/laucis, might not be se- 

 lected as the best expression of the suffusion of interroyatiunia.^ it is 

 quite certain that its peculiar bloom at once calls up to the inind of the 

 observer, a superficial deposit like that upon a cabbage-leaf which a 

 touch of the finger would serve to remove. 



The second feature of Fabricius' description, cited to prove his in- 

 terrogfitioniA to be umbrom. is the " striga punctorum nigrorum," 

 and in reference to these, it is asserted that " uinbrosn of the two spe- 

 cies, is the one distinguished in both sexrs by a band of disfincf bbi<:k 

 points rr-ixxinfj both vintj.s." True ; but Fabricius does not claim to 

 describe buth sexes, and indeed Edwards asserts that he knew but one : 

 nor dues he state that the black points are (/isfiw-t, and that they cyo.NS 

 both wings in a band, but simply that there is " a row of black points." 

 This requirement is fully met by intm-otjationis, and ti» show more is 

 superfluous. Even in the female a ri)w of points is visible, and might 

 properly be made a feature in its description, when compared with a 

 Vanessa where they are wanting. These points, instead of being of 

 specific value, are a generic feature, occurring in the (jrraptie, in 

 Fannns, comma, Drija't, mtci'ro(jiUionis, umbrosa and J-albam alike. 



If then, the glaucous shade and black points common to both of the 



