).] 



NEW-YORK MICROSCOPICAL SOCIETY. 



63 



eating the detached wood, which is further reduced to pulp in 

 the gizzard. They eat the wood for sustenance, as it is found 

 in the alimentary canal, giving this the color of the wood eaten 

 — light colored if the wood is clear and white ; dark if the wood 

 is red. 



On the Isthmus there is so much more moisture in the air 

 than here, that many of our seasoned woods, which here con- 

 tain only from twelve to eighteen per cent, of moisture, will 

 reabsorb more and become nearly as soft as green woods. And 

 in this condition they can be more easily eaten by the Termites. 

 This is especially true of White Ash, 

 one of our hard and valuable woods 

 here, but worthless there. The large 

 ducts, which constitute the spring 

 growth of this wood, render it espec- 

 ially easy for the Termites to eat, 

 and it is quickly attacked. In speci- 

 mens, Nos. 21, 22, 23 and 24 it will be 

 seen how the attacked wood is tun- 

 nelled without defacing the exterior. 

 It requires close attention for detec- 

 tion. Our common Whitewood is so 

 open grained that it also is quickly 

 attacked. White Pine is only used in 

 thin boards, but it quickly decays on 

 the Isthmus, and, of course, is then 

 attacked by the Termites. Yellow 

 Pine is attacked as soon as the fibres 

 are softened by decay. Spanish 

 Cedar, which is allied to Mahogany, 

 has a strong and pungent odor, and 

 it is said to be exempt from these 

 attacks. This wood is used for the 

 floors and interior finish of houses in 

 many parts of South America on this 

 account. 



The construction and repairing of the galleries, already men- 

 tioned, is performed by the workers, guarded, and in one sense 

 directed by the soldiers. The galleries examined were con- 

 structed of minute pellets of clay, sand or small particles of 



Fig. 6.— Repairedfgallery of Eu- 

 termes. Dotted lines show where 

 the gallery was broken away. 

 The central globular mass, an 

 ant, pinned in position for ex- 

 periment, and entombed with 

 cemented material by the work- 

 ers. The curved portion on the 

 right, a new continuation of the 

 gallery built around the obstruc- 

 tion. (Natural size.) 



