240 Studies in the Theory of Descent. 



SMERINTHUS OCELLATUS, LINN. 



The green eggs much resemble those o 

 as also do the newly hatched caterpillars, which, as 

 in the case of this last species, are entirely without 

 markings. As with Populi, the markings are 

 formed in the course of the first stage, and are 

 distinctly visible before the first moult. The long 

 caudal horn is of a red colour. 



After two to three days the caterpillars moult, 

 their length then being one centimeter ; the seven 

 beautiful oblique white stripes, and the fine white 

 subdorsal line, are more strongly pronounced, the 

 latter becoming broader in front. They differ 

 from Populi in having the oblique stripes united 

 in the dorsal line. 



The second moult occurs after another three 

 days, and brings no important change ; only the 

 fine subdorsal line becoming somewhat fainter. 

 Neither is the third moult, which takes place four 

 days later, associated with the appearance of any 

 essentially new character. The oblique stripes 

 remain as before, but their upper portions now 

 stand on a somewhat darker green ground colour, 

 whilst the subdorsal line vanishes, leaving distinct 

 traces only on the three or four front segments. 



The fourth moult follows after a period of seven 

 days, and my bred larvae underwent scarcely any 

 alteration in marking. Only small differences in 

 coloration became perceptible in the head and 



