REPORT OF THE SOCIETY 109 



passage to the mouth of the burrow where it projects itself sufficiently to expose 

 the head and thorax and perhaps a segment or two of the abdomen. The 

 remainder of the case is held secureh' within the tunnel walls, anchored there 

 by the numerous, sharp, chitinous dentations which protrude from each seg- 

 ment. Exposed to the air and free now to expand, the case quickly dries and 

 cracks up along the clear-cut furrows enclosing the appendages; then by a 

 number of violent pulsations, the head shell splits open and the moth quickly 

 slides out from the case, pulling antennae, wings and legs from their covers, as 

 it goes. The whole operation of emergence takes but a few minutes. As soon 

 as liberated the moth expels a quantity of thick, white, liquid excrement, aind 

 crawling lazily on to the bark, proceeds to dry and stretch its wings. These are 

 quite small, flaccid, and much crumpled when at first they come from their 

 covers, but ass-ume their naturel form in about fifteen or twent\' miriutes. 

 When quite dry and fully stretched the moth folds them tent fashion over the 

 back. 



A good example is given here of protective coloration. The dark grey body 

 of the moth, with its mottled wings, resting motionless on the roughened grey 

 bark of the oak presents an object of natural camouflage which may deceive 

 the eye of even a trained observer. 



The moths emerge for the most part in June. A careful tabulation was 

 kept of the adults as they came from the trees each day, by collecting the 

 empty cases of the escaped imagines. About two hundred and fifty oaks were 

 under observation and these were visited twice daily, morning and night. 

 The first adult seen and pupal case collected was on June 4. On June 6 and 

 9 respectively, eight cases were taken, while on the 13th ten were gathered. This 

 number then decreased rapidly until on the 29th one case only was found. 

 Total of moths collected 59, in the proportion of 84.8% females and 15.2% 

 males. 



While it is the general rule for pupation to take place in the fall of the 

 year, it would seem that this does not alwaj's occur at that period. On two 

 separate occasions transformation did not take place until the following summer. 

 The two particular instances referred to were under close observation and there 

 was good reason to believe that the larvae were shortly to pupate, because the 

 frass which had been observed issuing regularly for the past two seasons now 

 began to be thickly matted and appear in very coarse pellets, a good indication 

 that the tunneller's work was nearing completion. In due time this work ceased 

 altogether and after a brief period of about three weeks both pupal cases 

 appeared. 



According to some investigators the larva makes its pupal bed near the 

 mouth of the tunnel and in order to prevent parasites, ants and marauders 

 from finding an entrance, it constructs a crude barracade of chips very near 

 the exit through which the pupa forces its way later . . Field observations at 

 Queen's Park for the past three or four years do not confirm this. The habit 

 of forming a barrier of small bits of excelsior cut from the tunnel walls is com- 

 monly met with among certain members of the coleopterous larvae, as for example 

 Saperda calcarata Say, and Cyllene robiniae Forst., but has not been associated 

 with P. macmurtrei. 



Emergences occurred under cover of night or very early in the morning, a 

 fact which was substantiated bj^ the adults and empty pupal skins being found 

 only during the morning rounds. This arrangement has decided protective 

 advantages, since a wriggling pupa, moth in process of emergence, or one moving 



