248 Studies in the Theory of Descent. 



Variety III. Blackish-green or greenish-black 

 (Figs. 10 and n, PI. III.); subdorsal line with 

 blackish-green border above, gradually passing into 

 a light green ground-colour; spiracular line,chrome 

 yellow ; head and prothorax, greenish-yellow. 



Variety IV. Light green (Figs. 4 and 12, PI. 

 III.) ; dorsal line quite feeble ; subdorsal broad, 

 only faintly edged with dark green ; subspira- 

 cular line, faint yellowish ; head and prothorax, 

 green. 



Variety F. Brownish-violet (Fig. 8, PI. III.) ; 

 the black dorsal line on a reddish ground either 

 narrow or broad. 



From these five varieties we see that the dif- 

 ferent types do not stand immediately next to' 

 one another ; they are, in fact, connected by 

 numerous transitional forms, the ground-colour 

 varying greatly, being dark or light, yellowish or 

 bluish. (Compare Figs. 4, 5, 7, and 12.) The 

 markings remain the same in all, but may be of 

 very different intensities. The dorsal line is often 

 only very feebly indicated, and the subdorsal line 

 is frequently but faintly edged ; the latter is also 

 sometimes deep black above and bordered rather 

 darkly beneath, the sides then being of a dark 

 green, often with blackish dots on the yellow 

 spiracular line (Fig. 5, PI. III.), this likewise 

 being frequently edged with black. Only the 

 horn and legs are alike in all forms. The green 

 ground-colour passes into blackish-green, greenish 



