78 BULLETIN 15 7, U. S. NATIONAL MUSEUM 



The local form of this butterfly is more or less midway between the 

 form found in southern New England and New York and the form 

 occurring in Arizona (arisonensis) , though slightly nearer the 

 former. 



BASILARCHIA ARCHIPPUS ARCHIPPUS (Cramer) 

 ViCEEOY 



Plate 6, Figure 1 



Occun^eiice. — Locally distributed, but usually common where it 

 occurs, and in some places abundant. It is found in moist meadows 

 with small scattered willows, on hillsides with a growth of small 

 poplars, and, when numerous, along roadsides. It occurs frequently 

 in the open -fields along the Eastern Branch where willows or small 

 poplars grow, in moist hollows with willows at Silver Spring, and 

 abundantly in the meadows 2 miles west of Cabin John, where late 

 in summer it is to be seen especiall}^ along the roads. 



Hcthits. — In life the viceroy is not nearly so similar to the monarch, 

 or milkweed, butterfly {Danaus 'plexipjjus, pi. 6, fig. 4) as it appears 

 in collections. The monarch is a wanderer over open and more or 

 less flat country, while the viceroy keeps rather strictly to moist hol- 

 lows in meadowland, or to certain spots in scrubby hillside pastures, 

 or to bushy roadsides. The flight of the two is very different. The 

 lazy flapping of the monarch alternating with a seesawing glide, 

 during which the wings are held at an obtuse angle with each other, 

 is readily distinguishable at any distance from the quicker and more 

 nervous flapping of the viceroy and its straight glides with the wings 

 held horizontally. 



Where it is few in numbers the viceroy is a rather inactive butter- 

 fly, and the females are always more or less inert. It spends much 

 of its time resting on a leaf with the wings closed, and it is often 

 seen sunning itself with the wings horizontally expanded and the 

 fore wings drawn well back. When startled it seldom flies far, and 

 as it is not very shy it is easily followed and captured. The males 

 constantly make little excursions, flying out for 100 feet or so over the 

 open fields and then returning. Because of its inertness it may pass 

 unnoticed even when it is really rather common. If present it may 

 readily be found by beating the willow bushes and adjacent herbage, 

 which causes it to reveal itself. 



When abundant, however, and especially at the end of the season, 

 it becomes quite a different butterfly. The males leave their home 

 areas and are found scattered along the roads, basking in the sun, 

 fighting with one another, and darting savagely at any large grass- 

 hopper or dragonfly or other insect that comes near. If startled 

 they fly out over the fields at a height of 3 or 4 feet above the ground, 



