12 Journal New York Entomological Society. [Vol. XX. 



warmer climate of the transition zone. It seems plainly a circum- 

 polar species driven south by the glacier but returning immediately to 

 the colder climate as the glacier retreated. Where it has been found 

 by my friends it has been on hard beaten paths, on stony banks at 

 some distance from water, on the road above tree line on Mt. Wash- 

 ington, on bare rocks at Mt. Desert, Maine. The great number of 

 varieties into which it divides are in keeping with the idea of various 

 colonies isolated at different times by the alternating glacial action 

 and devoloped since glacial times in their present isolated homes. 

 Its failure to establish a home in the Catskills for instance, over 

 which it must have roamed at some time during the retreat of the 

 ice, is accounted for by its lack of adaptability. 



C. i2-guttata, distinguished from other species by its more de- 

 pressed form, has also an allied species in the old world, and like 

 longilabris occurs from ocean to ocean and extends north on the 

 Atlantic Coast to Newfoundland, but unlike that species has become 

 established also in the transition zone. Moist roads, damp low places, 

 are its favorite habitats. This species may even be found in the 

 upper austral zone where cold wet sandy roads with humus mixed 

 afford suitable breeding places but does not ever become abundant. 



Its distribution is readily accounted for on the same theory as 

 that of longilabris with a greater adaptability to explain its wider 

 range. The stronger differentiation of the Pacific variety of this 

 and other species may be due to a separation caused by the Sierra 

 Nevada even previous to the glacial period. The close relation be- 

 tween this species and rcpanda assumed by some authors seems to me 

 erroneous. They differ in form and outline, in maculation, and 

 remarkably in habits and distribution. 



C. purpurea with its numerous varieties occurring in nearly every 

 part of the United States and Canada is a puzzling complex, but is 

 nevertheless soluble by the factors I have suggested. It is evidently 

 capable of immense variation and adaptable to a variety of climates, 

 though quick to respond to a change of climate by a change in color 

 or marking. It has no extreme southern form nor any relative in 

 South America but has its old world prototype. On the Atlantic 

 Coast as variety limhalis it extends from Newfoundland south to 

 West Point and Ramsey as Mr. Sleight showed us last season ; as 

 typical purpurea it flourishes in Connecticut, New Jersey and south 



