NYMPHALINAE : BASILARCIIIA ASTYANAX. 283 



Dimorphic forms, etc. For the form proserpina, see the next section, where it is 

 (liscussed as a hybrid between this species and B. arthemis. 



'I'liat iiybrids between this species and B. arciiippns also occnr is rendered probable 

 l)y tlie remarks of Mr. Mead (Can. ent. , iv : 217) , who fonnd an astyanax on wliose upper 

 surface tlie blue was supplanted by fulvous "except in the marj^inal lunules, which are 

 white witli a faint bluisli tinge ," and also of Grey (Ibid. , xi : 17) , who says he possesses 

 "a melanitic form of disippus [archippus] with all the markings of Ursula [astyanax] 

 on the under surface." 



Egg (64 : 12). Surface smooth, with deep cells of a rounded ovate form, but angu- 

 lated and of the same size as in the previous species ; the thread-like filaments are sim- 

 ilar to those of that species, but are slightly curved at tip and are longer near the 

 summit of the egg than on the sides, being .1 mm. long at the summit, and about .06 

 mm. long on the sides. Micropyle, .154 mm. in diameter. Color when laid, shining, 

 bright yellowish green, afterwards becoming blackish in the middle and green and 

 yellow on opposite sides. Height exclusive of spines, 1.12 mm. ; width, 1.18 mm. 



Caterpillar. Third stage. Head paler brown than the body, heart-shaped above, 

 beset around the sides with little tubercles. Body bi'own above, whitish beneath, 

 with an oblong, triangular, whitish patch on the back of the fourth to seventh abdo- 

 minal segments ; two little blackish tubercles beset with very short spines on the top 

 of the second thoracic segment. Length, 15 mm. (After Harris.) 



Fourth stage. The tubercles have now become elongated; the top of the second tho- 

 racic segment has become distinctly pale or whitish, and the white patch on the back 

 is larger; there is a whitish elongated triangle extending along the sides of the hinder 

 extremity, from the hindmost feet to the side above the penultimate feet; there are 

 oblong tubercles or elevations in pairs on the top of the third thoracic, second, seventh 

 and eighth abdominal segments. Length, 32 mm. (xVfter Harris.) 



Last stage (74 : 17, 21, 25). Head (78:30) brownish red, with a moderately broad, 

 obscure, pale, flesh-colored band, passing down the front on either side of the middle, 

 the punctures paler; tubercles of the outer edge pale, the others partaking in gen- 

 eral of the color of the region they are in, the lai'ge one on the summit of each 

 hemisphere, which in this species is very nearly spherical with small projections, 

 dark brown ; a few very short, erect, pale hairs on the front of the head. Basal joint 

 of antennae pale luteous, second joint dark castaneous; ocelli black. 



Body smooth. First thoracic segment very pale, dull purplish, marked slightly with 

 blackish ; prominent parts of the second and third thoracic segments paler, between 

 them of ten mottled with paler purplish, livid and blackish, at other times like the parts 

 about, but obscured a little with dull purplish brown ; first to third abdominal seg- 

 ments dark reddish brown, the first tinged with olivaceous, the sides of all three Avith 

 a narrow, whitish, substigmatal band, sometimes tinged very slightly with purplish, 

 sometimes very distinct or lively in color, occasionally of a creamy tint; the third 

 abdominal segment has a subdorsal, pale purplish, bent line, the angle outwards; the 

 fourth is marked above with very dull, pale purplish, the fifth and the dorsum of the 

 sixth of the same color, the latter mai-ked with fuscous ; the rest of the fifth and the 

 seventh and eighth abdominal segments dark reddish brown, tinged and streaked faintly 

 with olivaceous; from the seventh segment backward there is a narrow, whitish, 

 substigmatal band, broadening between the eighth and ninth segments; the hinder 

 part of the body is blackish fuscous ; elongated tubercles of second thoracic segment 

 (86:60) blackish brown, cylindrical, almost the whole surface studded as closely as 

 possible with conical pointed warts, usually about as long as broad, directed a little 

 towards its apex, and at their tip curving in the same direction, giving the tubercle 

 a greatly thickened appearance. The tubercles are directed outward at right angles 

 to each other, but are not inclined forward or backward. The other laterodorsal 

 tubercles are usually white or Avhitish. The minute warts scattered over the body 

 are smooth, hairless, and usually shining steel blue, those upon the dorsum occa- 

 sionally colorless, and those beloAv the stigmata (sometimes) partaking of the color of 

 the surface on which tliey occur. Spiracles brown, encircled with black. Legs rather 



