1836 BUTTERFLIES BEYOND NEW ENGLAND. 



throughout Mexico and Central America and the northern parts of South 

 America. 



The butterflies are uniformly larger than the species of Eurymus, both 

 groups being remarkably monotonous in this respect, though not without 

 variation, but the bordering of the fore wing presents that remarkable 

 irregularity, by its recession in the median interspaces, at least in the male, 

 which gives it the dog's head pattern occurring 'also frequently in the 

 genera allied to Terias, such as Pyrisitia among those here described. 



In their transformations, so far as we] know them, they seem to closely 

 resemble Eurymus. 



ZERENE CESONIA. 



Papilio cesonia Stoll', Cram. Pap. exot. Megonostoma cuesonia Reak., Proc. eut. 



Suppl., 176-177, 382, pi. 41, figs. 2, 2 b (1791). Boc. Philad., ii: 358 (1861). 



Zere«e cesonia HUbn.jVerz. bek. sehmett., Colias coesonia Boisd.-LeC, LSp. Am^r. 



97 (1816) ;— Samml. exot. schmett., ii (1822-26). sept., 67-69, pi. 22, figs. I-.t (1829-30). 



Colias caeso)iiaGo(\.,Encyc\.m6th.,[xtSl, Fapilio sesonia Stoll', Cram., Pap. exot. 



98-99 (1819) ;—Boisd., .Spec. g6u. L«p., i:635- Suppl., 176-177 (1791) ;— Mart., Psyche, pi. 2, 



636(1836);— French, Butt. east. U.S., 127-128, fig. 5, 6 (1797). 

 fig. 32 (1886); — Edw., Can. ent., xx:21-24 

 (1888). 



Imago. Head covered above with mingled pale brown, pink, pallid and black hairs 

 and pink scales ; in front with pink-tipped pale yellowish scales. Palpi mingled yel- 

 low and pink, the latter predominating, with a few black hairs. Antennae heavily 

 clothed with pink scales, partially erect, the apex and whole under surface of the club 

 olivaceo-luteous. Thorax covered above with pale yellowish green hairs, beneath with 

 pale yellow and yellowish buff hairs ; the femora pale pink interiorly, very pale yel- 

 lowish green externally ; the tibiae pink above but yellowish beneath, as are the whole 

 of the tarsi, though the latter are more or less tinged with pink above. 



Wings above bright lemon yellow, sometimes suffused slightly, especially upon the 

 hind wings and the outer half of the fore wings, with orange. Fore wings vrith the 

 basal half above the cell, the basal third below it, black, heavily flecked with yellow 

 scales and short yellow hairs ; a round or transverse oval black spot, moderately large, 

 at the extremity of the cell; the outer border very broadly and generally very deeply 

 covered with chocolate black, which is limited interiorly by a very irregular line, 

 clear and distinct in the male, powdery in the female; it is formed of three nearly 

 equal divisions separated by tlie upper and lower median nervules ; the upper third is 

 strongly arcuate, runs from the costal margin to the upper median nervule, its con- 

 vexity outward, so as to just cross to the base of the third superior subcostal nervule, 

 and to terminate on the upper median nervule about as far beyond the cell as the width 

 of the apex of the cell ; the middle third crosses the median interspaces by at once 

 transferring the outer limit halfway to the border of the wing, forming thus a deep 

 quadrate excision of the marginal band which has a slight tooth baseward at the mid- 

 dle median nervule ; the third portion varies in the two sexes ; in both it traverses the 

 medio-submedian interspace in a strong curve, convexity inward, running from the 

 middle of the lower median nervule to a point on the submediau a little nearer the 

 margin; below this in the male it runs obliquely to the middle of the inner margin; 

 in the female it either continues in its original course or shows the same markings 

 as the male in a vague powdery form ; the tips of the subcostal nervures as they 

 strike the costal margin marked in white more or less extensively. Hind loings with a 

 pair of pale, faint, round orange spots, one at the middle of the apex of the cell, the 

 other beside it in the lowest subcostal interspace, due to the transparency of the 



