IMKMOIHS OF THE NATIONAL ACADEMY OF sriFNC'ES. 25 



Cii/orotkm of Si/xs/>/i/ii,r.^T\w larva of tho last staae has a tliit'k yrocn body, with the horns 

 and spines much reduced, while the lateral stripe is yellow, lleuee this form is protected simply 

 bv its o-reen color. Its young, freshly hatclied lar\ a. juduing from alcoholic examples, is plain 

 green, without stripes, but with long, large horns, nuich as in .1. />/'<■,,/(„■. 



Coloration of Eachs riiijxridlix. — We now liave an entirely diti'erent style of markings in 

 this genus. In the freshly hatched young of this polyphagous form there are no longitudinal 

 stripes on the pale sieiuia-bruwn body, })ut the abdominal segments 1 to 7 have each two narrow 

 regular parallel dark brown Ininds across the back, with either one or two short ones on the side 

 reaching up to or a little l)eyond the spiracular region. The body is very .spinose. the four 

 thoracic and the caudal horn very long and deeply forked, and pinkish. From what ancestral 

 forui this unusual style of markings has been derived is difficult to conjecture. The hue of the 

 body is similar to that of the .sheathing base of pine needles. 



This style of markings is retaincMl in the next stage, but the spines are somewhat reduced, 

 and are now black. At the second molting the larva enters on its third stage with no markings, 

 while the horns are pale, black at tips. After a third ecdy.sis the body is green (.sometimes 

 reddish brown): the horns are reddish and the spine-s are yellow, as ai-e the suranal plate and anal 

 leas and thoracic legs: the head is partly banded with yellow, while the midabdominal legs end 

 in yellow. The spiracles are in stage IV noticeable froiu the rich dark green ring in them, the 

 color of the pine needles. 



These hues and markings are apparently protective, the caterpillars, both the green and 

 brown forms, in the Kortheru States being most common on the white pine. 



In a larva of E. ji'-nflopc^Wwrn^ in the high mountains of the interior of Brazil. Peters figures 

 a form somewhat like E. imjwritdis. but with two violet dorsal bands bordered with white. This 

 kind of marking is exceptional and apparently unique in this subfamily. It lixes on a melasto- 

 maceous plant and also on the guava {Pyid'iim jfomffermri): neither of these plants is spiny. 



It is questionable whether the caterpillar of E. im2)e7'ial k oviguvdWy lived on the pine, though 

 when feeding among the needles it is not readily detected. 



t',)Iorafio>t in Citheronia. — Unlike Eacles, the two species of the present genus, the only ones 

 whose earliest larval stages are known, are not marked with l)ands either longitudinal or trans- 

 verse, or any spots. In C. regul!" and mpulGralis the body at birth is either dusky pale on the 

 upper side of abdominal segments four to six {C. regal i.-<), or pale yellowish lirown and dusky on 

 the dorsal side of abdominal segments five to eight (C. seju/leralifi). 



The markings, or rather their absence in this stage, throw no light tin the relationships of 

 this genus, whatever may be said of the arnrature. 



After the first molt C. rrt/alis is reddish and C. -vrpulcralix yellowish. Now. some very 

 interesting stripes appear in C. regalia. On each side of the back of abdominal segments one to 

 eifht are three short, dark, irregular longitudinal bands, the hnrext <f which is directed a little 

 ddii-ninird and extends under the xpiraclr. this hecoming the ohlique hand^ a characteristic color- 

 mark of this genus, not usually present in the Ceratocampid;e. Unlike the oblique stripes 

 in the majority of the Sphingidiv, these stripes pass from the front edge of the segments, and 

 also do not overlap on the succeeding segment. This is also the case with the corresponding 

 markings in the Saturuiida; (Telea, etc.). The two shorter upper bands are not retained, but 

 disappcirr with the second casting of the skin. 



In stage III the seven pairs of oblique stripes are dark above and pale beneath. They 

 probably harmonize with the dark twigs of the food tree. 



Those in C. sepalcralis arise in the same way. there being at first three, though more obscure 

 and irreo-ular. and in this species two are retained, only one being eliminated: there being on 

 each side a di.stinct straight dorsal stripe, besides the oblique one situated in front of the spiracles 

 which is not quite so long as in C. regal !". We thus see that colorntional features in these two 

 species appear to be more stable than the armature, since the two species under discu-ssion belong, 

 as regards the armature, to two quite different sections of the genus. 



