138 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



in size and form in bred specimens of robiniella. That which I have called 

 above the " first dorsal streak" in robiniella is the one which is so de- 

 nominated by Clemens; but, in fact, as I have elsewhere stated, there 

 is on the dorsal margin, much nearer the base, and in the darkest part 

 of the wing, another faint streak or spot which is only faintly indicated 

 by a paler or more silvery portion surrounded by a dark margin, and 

 which, in some lights, has a decided silvery hue. It is more distinct in 

 /Some specimens than in others, and is well shown in Professor Zeller's 

 figure. This faintly-indicated spot in robiniella becomes in texana, in. 

 amiiliicarpeoeeUa^ and in amorpJiceella a very distinct white streak, which 

 Dr. Clemens noticed as one point in which amphicarpeceella differed from 

 robiniella. Specimens (bred) of ampMcarpeoBella are also before me. This 

 variety is a little larger than robiniella^ of a richer reddish-golden hue, 

 and the marginal streaks have a brighter silvery luster. The single 

 specimen of amorpJiwella has no trace of a basal streak on the fold, nor 

 has robiniella usually, though a few white scales are sometimes sprinkled 

 on it. L. texana has a distinct white streak extending along the fold, and 

 in ampliicarpeoeella this streak is still longer and brighter. In addition 

 to what has been written above as to the true first dorsal streak (the one 

 faintly indicated in robiniella)^ it is proper to add that I have bred speci- 

 mens of ampliicarpeceella in which the dark color of the dorsal margin 

 ceased abruptly at about the basal fourth of the wing-length, and in 

 which the remainder of the dorsal margin to the fold and as far back 

 as the cilia is snowy white, only interrupted by a narrow oblique dark 

 brown dorsal streak, placed about the third of the wing-length, and rep 

 resenting the dark margin of one of the usual dorsal white streaks ; and 

 in other specimens the true first dorsal is as faint as in robiniella. Usually, 

 however, there is a greater or less proportion of white scales, intermixed 

 with the dark color of the dorsal margins. There is as much variation 

 in the size of the apical spot in ampMcarpemeUa as in robiniella., and some- 

 times it covers the entire apex, and in this respect both, like amorplue- 

 ella, seem to differ from texana. The marginal streaks in ampliicarpeoe- 

 ella are less oblique than in robiniella, but more so than in texana or 

 amorpliceella. The last costal spot in amphicarpeceella is smaller than in 

 texana, and has a small dorsal spot opposite to it, in these respects 

 agreeing with amorpliceella. In texana and amorpliceella, the first costal 

 and its opposite dorsal streak meet, and form a not very strongly-an- 

 gulated fascia ; in robiniella, as before stated, these streaks do not dis- 

 tinctly meet, but are connected by a silvery-gray line, and in amphicar- 

 peceella they are still more distinct. 



Thus the sjDecies or varieties differ in the size of the apical spot; but 

 as specimens of the same variety differ among themselves, this cannot 

 be considered specific, and, besides, texana and amorpliceella are not 

 known by a sufiicient number of specimens. They differ also in the 

 clistinctness of the true first dorsal streak, but neither is this specific. 

 They differ in the presence or absence of the basal streak, but its place 



