of the IVJiite Mountains. 621 



two countries ; upon the Alps, the lower limit of the sub- 

 alpine district is placed, by different botanists, at from 

 4000 to 4500 feet, and that of the alpine, at from GOOO to 

 6500 feet. Now, although Mont Blanc is in a latitude 

 north of Mount Washington by a degree and a half, yet 

 the isothermal and isochiinenal lines which pass respect- 

 ively through these two points, would, when compared 

 together, show, that a mountain elevation in Europe, to 

 have similar climatic conditions to those of the White 

 Mountains, ought to be placed to the northward of the Alps, 

 and would be found in just such a relative position be- 

 tween the mountains of Switzerland and Norway, as the 

 limits of the alpine and subalpine districts of the White 

 Mountains are found to be related respectively to those of 

 the Alps and Scandinavian mountains. And by these same 

 comparisons we may judge, that if the summit of Mount 

 Washington were somewhat less than 2000 feet higher, it 

 would reach the upper limits of the alpine district, or the 

 region of perpetual snow. 



• 



Chionobas semidea Edwards in Morris' Synopsis Lepid. 



N. Amer. p. 351. 



Chionobas semidea Scudd. Proc. Essex Inst. III. 169. 

 Hipparckia semidea Say, Amer. Entom. PI. 50. 



« « Say, Entom. N. Amer. edit. Le 



Conte I. 113, PI. 50. 

 « " Harris, Ins. Inj. to Veg. 3d ed. 



304, Fig. 126. 



Wings dull brownish fuscous tinged with ochraceous ; 

 fringe blackish brown interrupted between the nervure 

 tips with ochraceous, dark brown along inner edge of sec- 

 ondaries. Above: jPnwanes nearly uniform in tint; basal 

 half of costal edge with miimte alternate black and whitish 

 bars, the markings of the under surface indicated faintly 



