THE LEAD-CABLE BORER IN CALIFORNIA. 33 



in the cage. The cables were examined on September 13. No new 

 work was found in the battery cable, but considerable new work was 

 noticed in the alcohol one. Numerous attacks had been made on the 

 underside, two of which had penetrated the lead and were allowing 

 the alcohol to escape. These were filled with wax and the cables 

 returned to the cage. The cage was examined on September 21. 

 There was no new work, but the alcohol had escaped. Thirty-three 

 beetles Avere placed in the cage and the battery connections removed. 

 On October 6 the cage was examined and most of the beetles were 

 found to be missing. Two more holes were found in the alcohol 

 cable and numerous small borings. Both cables were cut into twos 

 and nine beetles were found inside of the battery cage which had 

 the battery detached September 21, Some were trying to bore out 

 at the ends. 



Taking the experiment as a whole, the results are indefinite. One 

 beetle bored a hole into the battery-attached cable and at least six 

 penetrated the alcohol-filled one. During the time the cage was in 

 use, however, 250 beetles were placed in it and practically all of the 

 boring was done by a few beetles from two or three lots. If any 

 particularly attractive condition had been created it seems as though 

 more boring should have been done. The experiment opens up a 

 new field, however, and should be continued this year (1922). 



Holes. — To determine if the beetles are attracted to holes already 

 started in the cable by other means, a section of a cable was punc- 

 tured and partially punctured by a number of holes, some shallow 

 and some nearly through the sheath, and placed in a cage. Forty- 

 five beetles were introduced into the cage on two different occasions. 

 Six males were found in the holes at various times but no females. 



Colors. — To determine the attractive effect of colors on the beetles, 

 sections of dead cable and sections of wood were painted in alter- 

 nating rings of reel, yellow, and green and placed in the large ex- 

 perimental cage. Over 1,500 beetles had a chance to attack these, 

 but none did. 



Feementation Experiments. 



Alcohol. — To determine the attractive effect of alcohol on the 

 beetles the following experiments were carried on in addition 

 to those mentioned under "Aerial cage " and " Battery cage." 

 Twenty glass vials 11 millimeters by ^0 millimeters were placed in 

 a cage. Ten of these were empty and 10 contained grain alcohol. 

 All were closed with cork stoppers. They were placed in the cage 

 in two rows, empty alternating with alcohol-filled, and cork end 

 alternating with glass bottom. Forty-five beetles were placed in the 

 cage on two different occasions. One cork of an alcohol-filled vial 

 was attacked and bored several times and two others slightl}^ bored. 

 2047—22 5 



