180 Journal New York Entomological Society. [Voi. xvii. 



stone and fiercely attack the strange Tctramorium. The workers of 

 the parasitic species seized the Tctramorium by the head or thorax, 

 curled their bodies around the latter and tried to pierce their armor 

 with the sharp, sickle-shaped mandibles. Other alpUius workers made 

 for the strange larvae and pupae and began to carry them into the 

 nest. This they did rather clumsily, but they showed themselves to 

 be very familiar with the position of the nest-entrances. The 

 strange Tetramorimn that were not engaged in mortal combat with 

 the alpimis hurried away over the stone in the opposite direction with 

 such larvae and pupae as they could rescue. The hosts of the alpvnns 

 were not seen to throw out the strange pupae and larvae brought into 

 the nest by their parasites, as happened in the similar experiment 

 performed by Forel on a colony of the typical hnberi. 



7. August 18. In the same locality I found under a small flat 

 stone a colony very similar to (4). It comprised about 100 alpimis 

 workers, a very few Tetraniorium and two or three larvae, presumably 

 of the latter species. These ants, too, appeared to be merely a 

 foraging troop hiding under a stone. 



Several of these observations tend to confirm Forel's belief that 

 S. hiiberi is still, unlike the more degenerate 6". testaceus, able to 

 make dulotic raids on strange Tctramorium colonies. This is indi- 

 cated by the behavior of the huge colony (6) and by its size, which 

 so far exceeded that of any of the Tctramorium colonies I have seen, 

 that I can only suppose that it had grown by repeated slave-making 

 forays. The two isolated bands of alpimis workers (4) and (7) also 

 point in the same direction, and suggest that the forays of this ant 

 may be nocturnal and that the dulotic troops may hide under stones 

 during the hot hours of the day. This may, perhaps, account for the 

 fact that the forays of this rare and diminutive ant have hitherto 

 failed to attract attention. 



III. Anergates atratulus Schenck. 



On finding such numbers of Tctramorium colonies on the western 

 slopes of the Matter valley, and especially after coming upon the colo- 

 nies containing the Strongylognathus described in the preceding 

 paragraphs, I naturally began to look for the extraordinary Aner- 

 gates, which is also a parasite on Tctramorium. After much search 

 I succeeded in finding it in the locality south of Zermatt where I 

 first observed 5". alpimis, in two nests which may be briefly described : 



