March, I902.] Herrick : T.ife-Habits OF Oncideres Texana. 17 



wood. They grow rather slowly and apparently little wood satisfies 

 them. In one branch, three-eighths of an inch in diameter, two larvae 

 came to maturity in galleries not over five inches long. Of course the 

 two galleries occupied nearly the whole branch, only the thin bark 

 and a thin partition wall remaining. 



The larvae exist in these cut-off branches one year in most cases 

 and then pass into the pupal stage within the gallery. Some larvae 

 certainly pass another winter in the branches. These are evidently 

 those that for some reason have not grown rapidly, owing possibly to 

 insufficient nutriment. Among several branches examined in January, 

 1902, two larvae were found that had not changed to the pupal form. 

 They were not over two-thirds grown and most certainly will remain 

 as larvae until warm weather. 



Before the larva changes to a pupa, it cuts a pinhole in the bark 

 near the end of the gallery, and closes up the opening of the burrow 

 behind with long thread-like shavings. 1 he pupal cell is thus fur- 

 nished with an opening to the outside for air and egress when the 

 proper time comes. 



Piipce. — On account of my intense desire to obtain the adults, the 

 larvae were disturbed as little as possible and consequently the exact 

 time of change to the pupal form is not known. It was some time be- 

 tween October 12 and November 12, 1901. On the former date, two 

 were examined and found still in the larval state. On the latter date 

 they were pup«. This gives approximately one year in these two 

 cases for the development of the larvre. 



The pupae are also white with short dark-colored spines on the 

 dorsal sides of segments. They vary from seven-sixteenths to five- 

 eighths of an inch in length and lie in burrows in most cases as de- 

 scribed above until some time during the following summer. The 

 pupae under observation at this time, January, 1902, developed from 

 eggs laid in October, 1900, have not changed to the adult form with 

 one exception, and can hardly be supposed to do so until warm weather. 

 The one exception noted was the case of a pupa that had attained the 

 adult form in the autumn but for some reason was not able to issue 

 from its cell and died. So it is possible that in some cases one year 

 may complete the life-history. 



In October of this year I found many larv^ in branches of oak 

 and the adults were then depositing their eggs in a tree near by. This 

 fact puzzled me at the time but when I learned that the pupae lived 



