THE CANADIAN ENTOMOLOGIST. 79 



DESCRIPTION OF THE LARVA AND PUPA OF 

 AULAX NABALI. 



BY THOMAS W, FYLES, SOUTH QUEBEC. 



The tall White Lettuce, Nabalus aitissitims, Hooker, is a striking and 

 graceful plant. At Quebec it is found in glades and on the edges of 

 woodland roads. Its wand-like stems rise sometimes to the height of six 

 feet, and end in panicles of greenish-white or pale straw-coloured flowers. 

 The stems are hollow, but have a lining or inner coat of white downy 

 pith, which in the summer is sometimes found to be broken with 

 discoloured warts. Late in the fall, when the stems of the plant have 

 become indurated and the pith has dried up, the warts are found to have 

 developed into galls of the size, shape and colour of grains of hemp. 

 I have found them in the stems from about six inches above the ground 

 up to a height of three feet or perhaps more. Sometimes they appear in 

 clusters, sometimes in rows, and sometimes singly at intervals. The 

 proper inhabitant of each of these galls is a footless, spindle-shaped grub, 

 one-eighth of an inch long. In colour it is like white wax, with the mouth 

 organs brown. It is more pointed at the head than at the other extremity. 

 It lies curled round in the gall. 



Towards spring the pupal change takes place. This change may be 

 hastened by warmth ; the specimens I have kept in my study are now 

 (January 9th) passing through it. A week or two after the change 

 the pupa is of compact form, white, waxen, with amber-coloured eyes. 

 The head is small, the thorax large and convex, and the abdomen ovate 

 and closely joined to the preceding part. The legs are drawn up by the 

 sides of the thorax, and the tarsi are stretched backwards under the body. 

 The antennse (beautifully translucent) are turned under the head and 

 extended between the tarsi, reaching nearly to the end of the abdomen. 



The perfect insects were described by Dr. Brodie, of Toronto, in the 

 25th volume of the Canadian Entomologist, p. 12. I copy his descrip- 

 tion for the benefit of those who may not have the volume at hand : 



"?. — Length, 2.50 XX. Antenna- 13-jointed; uniform brown ; head 

 "and thorax black; abdomen shining brown, with a large anterior dorsal 

 " spot black ; all the tibias, femora and tarsi brown, a little paler than the 

 " abdomen ; wings ample, veins well-defined, hyaline, iridescent at certain 

 " angles." 



" Abdomen of ,$ darker brown, and without the dark dorsal spot. 

 " From numerous specimens." 



