220 Journal New York Entomological Society. [Vci.xviii. 



and larvse, may have comprised about a thousand individuals. The 

 nest was composed first of the central, cylindrical cavity of the main 

 branch, corresponding to the pith cavity, and second, of concentric 

 stories corresponding to the layers of the wood. Each of these 

 stories was very low but very extensive and formed a single great 

 labyrinthine hall rather than a number of separate chambers. The 

 stories communicated with one another and with the central cavity 

 and outer openings only by means of narrow passages. Strange 

 to relate, the nest was concentrated in the median layers of wood, 

 the outer layers being perforated only by the galleries of exit, the 

 principal one of which opened, moreover, through the central cavity 

 on the cut surface of the secondary branch. All the wood which 

 served the ants for protection was very hard." Several European 

 authors mention the occurrence of C. faUax also in hard, woody oak 

 galls. 



In 1879 Forel broached the question as to whether the American 

 forms of fallax have the same habits as the European type of the 

 species. From many personal observations, especially on the forms 

 ncarcticns, minutus, pardus, rasilis and discolor, and from notes of 

 correspondents on other forms, I am able to answer Forel's question 

 in the affirmative. Our forms are all very timid ants, living in small 

 •communities in galleries and chambers which they excavate in dead 

 wood and according to the same pattern as those described by the 

 Swiss myrmecologist. Usually the wood of standing trees is pre- 

 ferred by the ants, probably because this is in the immediate 

 vicinity of their food supply, which consists very largely of the 

 excreta of aphids and coccids on the leaves and bark. The oak is a 

 favorite tree in America just as it is in Europe, probably because in 

 addition to nourishing a large number of Kcrmes and other phytoph- 

 thorous Homoptera, its leaves and galls give off a sweet secretion in 

 very small droplets that can be lapped up by the ants. The cavities 

 of the hard galls of Holcaspis, which cling long to the oak twigs, are 

 favorite nesting places, especially for incipient colonies of the forms 

 discolor and rasilis which abound on the live oaks (Oiicrcits vir- 

 giniana) of Texas and the other Gulf States. In the northern states 

 nearcticiis is also fond of oaks and chestnuts, but in the warm pine 

 barrens of southern New Jersey, it is quite common in dead branches 

 of the pitch pine (Piiiits rigida) or in its old cones that have fallen 



