402 THE BUTTERFLIES OF NEW ENGLAND. 



cremaster black; wall of the preanal button luteous, bordered inwardly with blackish. 

 Length, 25-28.5 nim. ; breadth of ocellar prominences, 4-4.5 mm. ; height of thorax, 

 9-9.75 mm; breadth of body, 9.5-9.75 mm. ; height of abdomen, 8.5-9.5 mm. 



The above describes the usual form, but there frequently occurs an individual of a 

 gray appearance, so dift'erent in general aspect as to merit a special description. 

 Whole body speckled gray, formed by blackish fuscous spots and streaks on a livid 

 white ground, the paler color sometimes tinged with faint purplish; the upper and 

 most of the under surface of the ocellar prominences are black ; the sides of the dorsal 

 tubercle of mesonotum are also black, but the posterior flank and the superior edge are 

 pale and from the anterior end a narrow, obscure, pale band runs toward either ocellar 

 prominence, and from the posterior end a faint, interrupted, pale, dorsal streak extends 

 over the abdomen; the apical half of the tongue is black and the nervure tips are 

 marked by a pale dot; on the abdomen there is a broad, dusky, ventral band and a nar- 

 row, dusky, stigmatal stripe ; the laterodorsal tubercles are black at base, red at apex, 

 tipped with black ; the other warts and tubercles are wholly black ; the upper edges 

 of the cremaster are pale, the lower black. 



Geographical distribution (20:5). This butterfly is apparently dis- 

 tributed over the entire breadth of the northern hemisphere below the 

 Arctic circle, as far as the thirtieth parallel of latitude. It is reported 

 in the Old World from England* and northern Spain to Amoorland 

 and Japan, including the Himalayas on the south in Sikkim and Bhutan. 

 In the New World it extends from Alaska (Dall, Kennicott, Edwards) to 

 the Athabasca region (Geffcken), Moose Factory (Weir), Labrador 

 (Christoph, Moschler), and Newfoundland (Gosse) ; and from South 

 Carolina (Gibbes), Georgia (Abbot), north Florida (Chapman) and 

 Bermuda, "very rare; one specimen seen" (Jones), to California and 

 Mexico as far as Cordova (Salle), near Acapulco at an elevation of 2000' 

 (Behr), and Oaxaca (Godman and Salvin). Godman and Salvin even 

 obtained two specimens on the table lands of Guatemala near Antigua and 

 Duenos, and Boisduval and LeConte state that it is found in Colombia ! 

 It occurs sparingly throughout the central plateau region of the United 

 States, and is rare throughout the southern states. 



It is found in nearly equal abundance through all parts of New Eng- 

 land, flies to but does not breed on the highest summits of the White 

 Mountains, and is nearly everywhere so numerous as to become positively 

 injurious on account of the damage done to some of our choicest ornamen- 

 tal trees. There is no remedy but to destroy the caterpillars wherever 

 seen, or the eggs if fortunate enough to find them. 



Haunts. The butterfly may be found nearly everywhere, but is 

 especially abundant in the neighborhood of woods, where it sports in 

 sunny nooks, and in spring time may be seen "hovering in numbers about 

 the sappy stumps of recently cut trees" (Saunders). In Switzerland it 

 feeds up to a height of 2,500 feet. 



Periodicity. Like many other butterflies, this is more or less irregular 



* It has always been very rare in England seen, excepting in 1872, when hundreds were 

 and for the last generation has scarcely been taken. 



