SPHINX LIGUSTRI. 317 



the earth to a depth of about 3 inches, and there make a cell of 

 fine mould, about 1-25 inches high by 275 inches in length, and 

 pupate therein (Clarke). The cocoon is very fragile, and is always 

 placed beneath the surface of the ground (Ransom). 



The pupal ecdysis. — The larva lies 8 or 10 days in its earthen 

 cell, and gets very shabby and dirty-looking, from the shrivelling 

 and darkening of the effete larval skin. Immediately on moulting, 

 the pupa measured 1*87^. in length, made up of (1) '63m., from 

 anterior extremity to end of wings ; (2) i^ins., to posterior extremity. 

 The segments are all very marked and rounded, with deep incisions, 

 the terminal is full and blunt, not tapering as in the mature pupa, the 5th 

 and 6th abdominal segments being especially large and globular. The 

 head stands out and somewhat apart, as it does permanently in many 

 Tineid pupae. The proboscis-case forms a square projection 'iin. 

 in length and width, but bent down somewhat already, markedly 

 bifid, and the two lateral halves easily separated. This case assumed 

 its permanent shape and length of about '28m. in about an hour. 

 Before moulting, the relative size of the segments had much changed, 

 the prothorax being large (from head pushed back into it ?) the first 

 abdominal very small, etc. The margin of the mesothorax against the 

 1 st spiracle was already brownish, as well as the flanges on the 5th, 6th 

 and 7th abdominal segments. After two hours the relative lengths 

 of measurement given above — (i)= - 63, (2)=i*24, had become — (1) 

 =i"i, (2)=o"]8. The abdominal spiracles were widely open, and 

 the winking movement of a membranous fold from the posterior 

 wall of the trachea a short distance within, was easily seen. There 

 are, in this species, no dark chitinous parts in connection with these 

 valves. These movements continued as long as observation could 

 be made. The period of closure became longer and longer. The 

 movements of the valves were synchronous with the vermicular 

 movements, but not with the pulsations of the dorsal vessel. 

 During actual moulting the valves were quite closed. As well as 

 the chitinous dark margin to first spiracle, the abdominal flanges 

 and the anal spine, there was also a slight chitinous tinting of the 

 dorsum of the mesothorax. The lateral stripes of the larva were 

 again very bright, and there are reddish spots (non-chitinous) at 

 the sites of the prolegs. The 8th abdominal spiracle yields as 

 strong a tracheal lining as the others, yet seems to be quite closed 

 and obsolete, as soon as this is withdrawn. The spiracles of the 

 6th and 7th abdominal segments are closed in about 15 minutes, 

 those anterior rather later, that on the 2nd abdominal segment in 

 about 20 minutes (Chapman. The newly-turned pupa is of a rich 

 green colour (Hellins). The changes that take place both externally 

 and internally in the larva of Sphinx ligustri during pupation were 

 worked out at length by Newport in his article " Insecta" (in Todd's 

 Cyclopedia of Anatomy and Physiology, 1839, pp. 853-994). The 

 figures are reproduced by Packard (Textbook of Entomology, p. 646) 

 and exhibit the arrangement of organs in the fullgrown larva, the 

 pupa, and the imago, in such a manner that comparison is easy. 



Pupa. — Of ordinary dark brown chitinous colour; length of a J 

 pupa 41mm., of a ? pupa 46mm., but may vary much from these 

 dimensions. It is a fairly straight pupa, i.e., no evidence of any 

 curve dorsally or ventrally at any part. The anterior extremity of the 



