180 



heaTi'ly marked ones are the characteristic forms of the nqrth. It 

 may be noticed in this connection that Kirby, by a comparison be- 

 tween a single specimen from Massachusetts with three from lat. 65° 

 N., separated the northern from the southern as being less heavily 

 marked. 



PiERis PROTODiCE, Boisd. and Lee. 



An examination of a large number of specimens in the collection 

 of the late Dr. Harris, in that of the Museum of Comparative 

 Zoology, and in my own, has shown me that this butterfly also enjoys 

 a wide geographical range, extending from Texas on the southwest, 

 Missouri on the west, and the mouth of the Eed River of the North 

 on the northwest, as far as Connecticut, and the southern Atlantic 

 States on the east. 



Coincident with these widely separ?ited geographical limits is its 

 wide range of variation, especially to be noticed on the under surface 

 of the secondaries, wherein it corresponds remarkably with P. olera- 

 cea. On the one hand, we have secondaries which are immaculate, 

 save some scarcely perceptible yellow scales on the discal nervule, bor- 

 dered by a very few scattered gray scales, a cluster of a few distant 

 gray scales near the border, between the first and second superior ner- 

 vules, and a dozen or so, more widely separated, similarly situated 

 between the second and third, and the edge of the wing light green- 

 ish-gray, with the fringe white. On the other hand, we find greenish- 

 gray scales spread quite heavily along the borders of all the nervures, 

 with the exception of the basal half of the superior and first inferior 

 nervules, which being clustered to^-ether toward the border into 

 arrow-head spots, and uniting together at their widest portion, form 

 a transverse zigzag bar ; in the place of the few grayish scales, be- 

 tween the first and second superior nervules, we have a large spot of 

 greenish-gray extending across the first superior nervule to the bor- 

 der ; a few scales only border the anterior half of the third superior 

 and first inferior nervules, and the yellow scales of the discal ner- 

 vule are only slightly increased in number, though the scales which 

 border it make a large spot, and are generally deficient in the green- 

 ish tinge ; the narrow border is interrupted by the darker scales 

 which form the swollen tips of the arrow-head spots. 



These extremes of variation I have found most generally in the 

 male ; in the other sex, I have not seen any specimens which had 

 these wings so nearly immaculate as that first mentioned, the nearest 

 approach to it being in specimens which discover a few scattered 

 scales along the borders of the nervures, the cross-bar of arrow-head 

 spots, reduced to an indefinite indistinct zigzag band, and tlie central 

 spot of yellow, bordered with gray scales quite indistinct. 



It may also be said of this species, as of P. oleracea, that these dif- 



