1462 THE BUTTERFLIES OF NEW ENGLAND. 



Fourth stage. Difl'ers from the preceding stage only in size, and in that the bright 

 spots of the head (80 : 34), which are so striking a feature of the mature larva, first 

 make their appearance as a pair of small, red spots just below the summit. Length of 

 body, 10 mm. ; breadth of same, 1.5 mm. ; of head. 1.7 mm. 



Last stage (77:9). Head (77: 8 ; 80 : 35) black, euliveued on either side by three 

 oblique streaks or spots of dull, inconspicuous, brownish red; one, the largest and 

 uppermost, extends from near the summit of the triangle to the upper outer angles of 

 the head, narrowing above; the others are roundish spots, one above and slightly 

 behind the other, occasionally united and then parallel to the uppermost on the middle 

 of the sides of the head ; the labnim is sometimes similarly colored at the base ; base 

 of the antennae and palpi livid, but the rest of the mouth parts black. Ocelli blackish 

 fuscous; elevated summit of head crowned with half a dozen small, bluut, conical, 

 black tubercles as broad as high. 



Body green, scarcely paler than the upper surface of the columbine leaves, becoming 

 5'ellowish in all wrinkles and aloug the lower border of the sides, so transparent that 

 the sex is easily determinable through the skin; a slender, pale yellowish, lateral line, 

 and owing to the transparency of the pellicle, only a darker green dorsal stripe; body 

 profusely covered with minute, whitish wartlets, from each of which arises a minute, 

 delicate, very short hair, as on the head, gi\ing a pale yellowish bloom to the surface. 

 Under surface scarcely paler green without much bloom, the legs and prolegs similar, 

 the tip of the former a little dull luteous. Si)iracles very pale luteous, inconspicuous. 

 Length of Ijody, 20 mm. ; breadth in middle, 4 ram. ; at first segment, 1.75 mm. ; of 

 head, 2.5 mm. 



Another description. The following was sent me in 1872 by Mr. W. Saunders: — Head 

 very large and prominent, nearly triangular in front, black, with a streak of reddish 

 white from each upper corner, extending to about the middle, and shaded on sides with 

 brown. There are also two whitish dots on each side, and one of the same immedi- 

 ately above the mandibles, the whole surface being roughened with minute tubercles or 

 granulations. Body above dull pale green, with a yellowish bloom occasioned by 

 the body being thickly covered with very minute yellow granules. A broken dorsal 

 line of deeper green, arising from the semi-transparency of the skin allowing the vis- 

 cera to show through. A faint [lateral] yellow line, with faint imperfect cross lines 

 of the same between the segments. Along each side close to under surface the color 

 becomes paler, with a more decided yellow tinge ; stigmata small, yellowish, not visi- 

 ble without a magnifier. The [first thoracic] segment is much constricted, giving the 

 head a much more prominent appearance than it would otherwise possess ; it has also a 

 narrow band of black on its anterior edge, close behind the head. Under surface pale 

 green with fewer yellow granules, feet and prolegs green, faintly tipped with brown. 



Chrysalis (85 : 30-32). Pale green, the wings, and to a certain extent the thorax, 

 not so pale as the other parts ; dorsal thoracic spiracles black ; body covered abun- 

 dantly with very delicate and short concolorous hairs ; cremaster tip and crotchets 

 testaceous. The tongue scarcely extends beyond the tip of the wings. Length, 14.25 

 mm. ; height of thorax, 4 mm. ; of abdomen, 3.5 mm. 



Comparisons. This butterfly and T. persiusare among the most closely allied of all 

 our species of Thanaos, and the recognition of their specific diversity is due in the first 

 instance to the skill of Mr. Lintner. T. lucilius difi'ers from persius in size, being on an 

 average considerably smaller, although individuals often approach each other in this 

 respect; but most in the rather conspicuous cinereous patch enclosed between the 

 viti-eous spots of the fore wiugs, — scarcely more than indicated in persius — and in the 

 lighter gray hue of the apical half of the same wing; the submargiual row of dark spots 

 recedes less from the outer Itorder on the lower half of the fore wing than in persius. 

 Lintner says that this is true of the extra-mesial [his "submarginal"] band, but my 

 specimens do not show this ; neither is there any difference (except individual pecul- 

 iarities) between the species in the comparative distance of the median vitreous spots 

 from the outer margin. 



