6 THE BUTTERFLIES OE NEW ENGLAND. 



accession of this stage is marked by an alteration of the pre^•iously uniform 

 brown to a brown which is of a rich purplish hue al)ove and dark yellowish 

 below, a change which seems to increase in intensity as growth advances. 

 In all other observed species, the change is somewhat different. In Eury- 

 mus philodice the uniform salmon is exchanged for a broad central band of 

 bright reddish orange, the opposite poles being yellow. In Ancyloxypha 

 numitor (66:35) irregular ragged patches of deep orange red make their 

 a[)pearance, encircling the egg with an archipelago of color. In Limo- 

 chores taumas the change is indicated, first by an alteration in the position 

 of the reddish flecks which now congregate in the upper half of the egg, — 

 a change which seems analogous to that referred to in Euphydryas phaeton ; 

 then l)y their collecting into streaks similar to those of Ancyloxipha numi- 

 tor, running irregularly in every direction ; and finally by their still greater 

 concentration into a broad spot, such as will next be described in Erynnis 

 metea. In this latter species the o})acity of the shell does not permit the 

 earlier stages to be witnessed and the first indication we have of anv change 

 is the appearance of an obscure fuscous band or cloud across one side of 

 the ef<r, extendino- from the extreme base a little way over the sununit, its 

 edges full and rounded ; afterward it contracts, occupying only the middle 

 of the side. 



There are then indications of at least three successive stages in this 

 period, viz., the polarity of the contents, the appearance of a central 

 annulus and the definition of a large lateral spot ; the first two correspond 

 to the f<irmation of the primiti^•e band and the last to the definite construc- 

 tion of the head. The duration of the first stage seems to be shorter than 

 that of the two succeeding ones, which are about equal in length. 



The Papilioninae, owing to the greater tenuity of the shell, offer better 

 opportunities for the examination of the contents of their eggs than the 

 Hespcridae. I have not, hoAvever, taken special note of their earlier life. 

 In both Papilio polyxenes and Euphoeadcs troilus the flecks and streaks 

 are dark green and reddish brown, and in the latter portion of this period 

 assume a definite arrangement, sketching in a Aague way the contour of 

 the enclosed larva, whose coil is visible from the summit of the egg ; the 

 dermal appendages seem to be formed at an earlier period than we should 

 anticipate, and through means of them the parts can be more readily recog- 

 nized ; in this instance, as I believe in all others, the colored flecks are more 

 clearly indicated on the side of the larva nearest the summit of the egg and 

 appear as little papillae or tongues, often spatulate in form, projecting from 

 the body and so overla})ping each other as to form an intricate net-work. 

 At this time, the close of the third period, the half-formed larva lies in a 

 coil around the egg-shell, reclining upon its side, its head and hinder ex- 

 tremity in juxtaposition and in the same plane. 



The change to the frnoih and final j^cyiod is a very short one, and in 



