TERMITES IN THE CANAL ZONE AND PANAMA. 15 



The history of the palm following inoculation was as follows: 

 At first there was no indication of anything wrong inside. Then 

 came a sudden rapid growth, which lasted a very brief time. The 

 palm then took on an unhealthy appearance, which became more 

 and more evident, so that people unaware of what had been done to 

 the palm remarked that it did not look well. Early in June there 

 was a browning and drying out of the tips of the leaflets, beginning 

 with those nearest the apes and gradually working downward. The 

 final collapse came July 7, i. e., almost six months after the inocula- 

 tion, the palm breaking off 2 feet from the ground level. 



The photographs show the palm after it had fallen. The close-up 

 of the trunk (PI. VII, B) shows at the base a slanting injury. The 

 extent of this wound is better shown in the accompanying sketch 

 (fig. 1), which gives the size and shape of the trunk, relation to 

 ground level, and the location, size, and shape of the wound. This 

 wound is of importance because it afforded entrance to termites. 

 During the time the palm was being watched this wound was sus- 

 pected of harboring termites, but there were no outward indications 

 of their presence, and to have cut into the injury in search of them 

 would have interfered with the experiment. There were no galleries 

 up the palm trunk, but, as was discovered later, termites were pres- 

 ent inside, having come up through the earth. 



The termites were very abundant inside of the trunk, where they 

 had formed a well-defined termitarium. Only soldiers and workers 

 were present, however, and there were no signs of queen chambers. 

 Five photographs were taken of a section through this termitarium 

 which illustrate well its character (Pis. VII and VIII). Special 

 attention is called to the runways in the shape of holes (PI. VIII, 

 B, O, D, E). At the widest part of the termitarium the termites 

 filled about one-third the width of the trunk, or about 6 inches, 

 but their tubular runways went to all parts, although none were 

 seen as far up as BB of the sketch (fig. 1). 



All of the tissue of the termitarium was abundantly supplied 

 with live nemas. Individual termites were carefully picked up and 

 washed in water, and by this means many live nemas which had been 

 clinging to their bodies were recovered. 



Since these termites had only a secondary termitarium in this 

 palm, they must have had the main one elsewhere, and probably 

 members of this same colony visited other palms in the neighbor- 

 hood. The possibility of mechanical transmission of nemas to 

 lealtoy palms by the termites is thus seen to be great. They may 

 De carried in any stage, including eggs. Likewise, since in this case 

 nemas were also in the roots, and it has been shown that nemas will 

 ive in the soil about an infested palm,, termites are well able to 

 become soiled with live nemas in the earth, and thus bring the in- 

 fection to other palms. 



The photo of section CO (PI. VII, 0), which is the upper side, 

 shows a part of the termitarium (indicated by an arrow) . 



After the trunk had been cut into four parts, as shown in the 

 ketch (fig. 1) (10 inches, 8 inches, 11 inches, and 11 inches), at 

 1 p. m., July 7, 1922, the four segments were left in the room till 

 next day. At 8 a. m., July 8, Zetek found along the face of the 

 second section (from top) a covered runway or gallery 7 inches. 



