192 THIRTIETH REPORT ON THE STATE MUSEUM. [80] 



the white streak with which it is marked, shorter and nar- 

 rower than in the European, and entirely wanting from the 

 middle branch [vein 3]. These are the only differences ob- 

 servable, and they are too slight to afford grounds for their 

 separation." 



In addition to the two examples in my own collection, I am 

 indebted to the kindness of Mr. von Meske for the opportu- 

 nity of comparing two examples of N. dictcea from Germany, 

 and two from Racine, Wis. 



In the European, the white stripe which traverses the 

 brown anal patch very near the margin, commences in cell 1, 

 within the internal vein, and is continued until near or just 

 beyond vein 2. In the American, this line is not so distinct, 

 and in an ex-larva example, from Albany, it is obsolete, being 

 represented only by a few white scales ; in another example, 

 it commences on the fold and continues to vein 3.. 



The bent white crossline pointed out by Dr. Speyer as 

 characterizing the American form, is not equally well marked 

 in all. In the Racine specimens, the line commences on the 

 internal margin, runs for a short distance parallel with the 

 general direction of the outer margin of the wing (not of the 

 anal angle portion), and curves inward toward, and is lost 

 in, the submedian fold. An exserted portion of the brown 

 patch lies inside of this white line on the submedian vein 

 (1 &). In the Albany example, the line is less conspicuous, 

 and the brown portion inside of it is barely indicated. 



The American examples, besides having the brown patch 

 larger, have also the brown border of the secondaries heavier 

 than the European, and continued to the apex. 



The comparison of Dr. Speyer of the length of the white 

 lines on the veins of the primaries is not sustained by the ex- 

 amination of other examples, as they vary in length and dis- 

 tinctness. In one before me, the white lines are of the same 

 length on veins 2 and 3 in another, shorter on 3. The more 

 conspicuous bifurcating white line on the submedian fold, also 

 varies in length. All the above lines also vary in their 

 breadth ; those on veins 2 and 3 being nearly as heavy as in 

 the European, while in the Albany example, they are much 

 more delicate. 



In the other markings of the wings I find no differences of 

 sufficient constancy to aid in the separation of the forms of 

 the two continents. 



