Dec, igio.] AVheeler : North American Camponotus. 219 



" C. marginatus [fallax Nyl.] lives in small formicaries and is 

 very timid. Roger, too, says that it is very timid and adds that it is 

 found throughout Germany on old oaks. I have seen only four nests. 

 The first was found near Zurich at the end of a dead oak branch 

 about 10.5 m. above the ground. The tree had been recently felled 

 so that I was able to study the nest at my leisure. The dead branch 

 was scarcely 5-6 cm. in diameter and the dead wood had acquired a 

 somewhat corky consistency. There was no hole at the broken end, 

 but there were two oval openings on the side near the end of the 

 branch. Two galleries, starting from these holes, united with each 

 other at a depth of 4 cm., whence a sinuous central gallery ran back 

 through the axis of the branch to a depth of about a decimeter and 

 terminated in three ampulla; in the form of chambers, whose inner 

 surface was not more than two square centimeters. During its course 

 this gallery sent ofT scarcely more than three or four short lateral 

 galleries, each of which also ended in a chamber. The chambers 

 and galleries were somewhat flattened in the same plane, that is to 

 say, their transverse section was generally elliptical. This was the 

 entire nest of these ants, a nest containing about 150 workers and 

 their larv?e. A second nest of the same size and very similar con- 

 struction was found at Vaud wholly in the corky layer of the bark 

 of a huge walnut, near the roots. A third nest was also found near 

 Vaud in an old post. I believe that it had been established by the 

 workers, which were still bringing to it their larvse and companions. 

 They were descending an old pear tree which had evidently been 

 their former residence. I did not open this nest. The fourth and 

 largest nest of marginatus which I was able to examine was in the 

 garden of the insane asylum at Vienna in one of the larger dead 

 branches of a Pauloziniia. This branch was two decimeters in 

 diameter. The ants had three exits, first, a main opening which was 

 made on the cut side of a secondary branch (dead also, of course), 

 second a smaller opening in an abrasion in the bark of the main 

 branch, distant about a meter from the first, and a third, very small 

 opening corresponding to the central or pith cavity of a small, broken 

 twig, which came ofT directly from the main branch between the two 

 other orifices. As the tree was felled soon after I had discovered 

 this nest, I broke up the branch and was able to examine both the 

 nest and the colony. The latter, consisting of workers, females, males 



