12 BULLETIN" 1232, U. S. DEPARTMENT OF AGRICULTURE. 



termes niger were found in the damaged 4-core cable by Mr. Wetjen 

 near Summit, Canal Zone, in November, 1921. Injury from termites 

 to the company's larger cable, which goes through a concrete duct, 

 has not yet been discovered. 



A. Cooper, manager of the Cristobal office of the All America 

 Cables Co., reported another case of damage to their cables by Copto- 

 termes niger 5.3 miles south of Cristobal, 660 feet from the nearest 

 splice, and in 2 feet of clay soil. The tape, rubber, and paper insu- 

 lation were also perforated (PI. VI, A). Workers and soldiers of 

 Coptotermes niger were collected from the center wall, Miraflores 

 Locks, Canal Zone, on May 15, 1922, by I. Molino and E. St. Clair 

 Clayton. These termites were damaging lead-covered, 5-core, T-wire 

 cables, 220 volts, alternating-current, at section 705. In 1 foot there 

 were 7 holes and in the next foot 3 holes. Six feet of cable had to 

 be replaced. Here there was a concrete cover, 2 by 3 feet, over a 

 small well 3 feet deep which communicated with a tunnel used for 

 cables that connected the two side sections, of which No. 705 was 

 one. Under this concrete cover was found some wood used for the 

 forms when the concrete was poured. This was infested with 

 termites. 



Specimens of the termites inside of the lead-covered cable were 

 collected as well as those in the wood. Specimens of the infested 

 wood, of the damaged cable, and of damaged insulation (PI. VI, 

 Z?, & } F) were collected. All of this damage was caused by Copto- 

 termes niger. 



This injury to lead-sheathed cables is what might be termed a 

 " local "damage. Such cases are not at all infrequent and occurred 

 also at Pedro Miguel and Gatun. If all the wood had been removed 

 at the proper time, however, there would have been none of this 

 damage. 



DAMAGE TO LIVING TREES. 



Cases of damage to living trees by Copiotermes niger are as 

 follows : 



On February 4, 1922, Zetek and Molino collected specimens in 

 avocado trees at Frijoles. Canal Zone. Galleries had been construct- 

 ed on the trunks of the trees (PL VI, G). These were rough, made 

 of clay, from 1 inch to 1| inches wide, and the cavity inside (or 

 hollow) one-eighth inch to three-sixteenths inch in diameter. The 

 termites also worked in the wood of the trunk, and a hole 4 inches 

 deep containing inhabited galleries was observed. Knot holes and 

 poorly pruned places in the trees where rot had already set in were 

 specially sought hy these termites. Soldier termites were very 

 abundant. 



Description of Plate VII. 



Interrelationship between nematodes* the termite Coptotermes niger, and the 

 " red-ring " disease op coconut palm trees : A, Palm C, Nurses' Quarters, Ancon, C. Z., 

 July 7, 1922. This cocouut palm had broken off about 2 feet from tbe ground and 

 had fallen over between 6 p. m., July 6. and 8 a. m., July 7. B, Closer view of same 

 palm, showing break at end of trunk and, at base, upper part of injury through which 

 termites Rained entrance into trunk where they had built a secondary termitarium. 

 Part of the trunk at break soft, rot-like in texture, abundantly infested with nematodes. 

 O, Smoothed face of section CC (see text fig. 1) of trunk. The red ring is very promi- 

 nent. Nemas were present in all parts of the section. In the lower right-hand 

 corner is a part of the termitarium. D, Covered runways of C. niger formed over- 

 night after trunk had been sawed up into four pieces. Larger diameter of trunk about 

 16 inches. Injury through which termites entered palm is seen in upper part of pic- 

 ture. 



