NYMPHALINAE: THE GENUS BASILARCHTA. 255 



band of white spots ; tlie basal portion of the Avings beneath and especially 

 of the hind wings is marked with clouded coloured spots. They differ from 

 butterflies of the genus Najas mainly in the broader mesial band (which 

 is generally absent from astyanax and wholly wanting in archippusj and 

 in the marginal markings. 



The eggs are very curious, being nearly globular, covered witli high 

 walled, hexagonal cells, from each angle of which arises a rather long, 

 stiff, tapering filament. According to Daube and Giirtner, those of the 

 European genera Limenitis and Nymphalis are similar. 



The larvae are exceedingly grotesque in appearance and present at the 

 same time a very tln-eatening asjject ; the head is surinoimted by a pair of 

 warty globular tubercles, and the fore part of the body is considerably 

 hunched and tuberculated, bearing, on the middle thoracic segment, a long, 

 stout, clubbed horn, bristling with short barbs ; the hinder segments of the 

 abdomen are also hunched and tuberculated, and the whole body is so 

 strangely and irregularly mottled with cream color and various shades of 

 green as to add greatly to the fantastic effect. They may be distinguished 

 from the caterpillars of Najas by the contraction of the first thoracic seg- 

 ment, the absence of profusely distributed minute papillae over the body, 

 and the reduction of all the tubercles of the third thoracic and second, sev- 

 enth and eighth abdominal segments, the latter less marked in the southern 

 B. eros than in our other species. 



The caterpillars of astyanax and archippus resemble each other most 

 strikingly, and probably in their earlier stages it would be almost impossi- 

 ble to distinguish them. The best points of difference will be found in the 

 summit tubercles of the head, and the elongated spinous tubercles of the 

 second thoracic segment. The former is almost globular in astyanax, no 

 higher than broad, and irregularly encircled near the summit with a fcAV 

 very small conically raised points which also are no higher than broad. In 

 archippus it is higher than broad, the sides straight, scarcely swollen, and 

 bear larger conical pointed warts higher than broad. The thoracic spines 

 of astyanax are much shorter than those of archi])pus, but of about equal 

 size ; they are more closely studded with tubercles, there being scarcely 

 any spot unfurnished with them, while many of tlie tubercles of the spine 

 of archippus are distant from each other by more than their owm diameter, 

 the tubercles themselves stouter and shorter, beins: seldom lono;er than 

 broad, while in archippus they are usually considerably longer, and often 

 ^nore than twice as long. See, however. Can. ent., iii : 52, 117. 



The above paragraph was written many years ago, since which time I 

 have been unable to examine more caterpillars of astyanax, but many of 

 arthemis, Avhich agrees better with it than witli archippus, and may inva- 

 riably be distinguished from the latter by the characters given in the table 

 beyond. Unfortunately I have not been able tt) make any direct compari- 

 sons between arthemis and astyanax. 



