THE DEGENERATE SLAVE-MAKERS. 495 



of the two species were recorded. Schmitt found a few specimens 

 while sifting vegetable mould for beetles near Beatty, Pa., and I 

 found it during the summer of 1905, in a rich, boggy wood near 

 Bronxville, N. Y. Here there were several fine L. curvispinosus 

 colonies nesting in the hollow twigs of elder bushes, and in three 

 of these colonies there were specimens of H. americanus. One con- 

 tained only a single worker, another six, and a third eight workers 

 and a queen of the parasitic ant. The latter insect was not ergatoid, 

 but decidedly larger than the workers, with well-developed ocelli and 

 a typical, though small, female thorax, showing distinct traces of having 

 borne wings. All three colonies contained larvae and pupae, presumably 

 of the parasitic species, but no Leptothora.v queens. When confined in 

 artificial nests the americanus were very inactive and paid no attention 

 to the brood. All the colonies were too small to admit of the suppo- 

 sition that they had been formed by repeated forays on the part of 

 Harpago.renus. This ant, in fact, has every appearance of having 

 reached a more abject stage of parasitism than its European congener. 

 In the same locality I found a mixed queenless colony of the yellow 

 L. curiispinosus and the black L. longispinosus inhabiting a hollow 

 elder twig. If a dealated queen of H. americanus happened to estab- 

 lish her colony in such a nest as this, we should have a case like Adlerz's 

 sublevis living with both L. acervorum and muscorum, but the inference 

 that this indicated repeated slave-making forays on the part of cimeri^ 

 canus would be erroneous. 



B. The Permanent Social Parasites. The ants included in this 

 group are all small and nearly all of them belong to monotypic genera. 

 The absence of workers makes it difficult to assign definite positions to 

 these genera in our classifications, which are based very largely on the 

 worker forms. 



i. Wheeiericlla santschii (Fig. 276). This is a small, dark-brown 

 species, the female of which measures 4-4.7 mm. in length, the male 

 only 3.5-3.8 mm. It was discovered by Santschi in the cactus fields 

 near Kairouan, Tunis, and lives in the nests of the most abundant of 

 all the North African ants, Monomorium saloinonis and its varie- 

 ties. The female Wheeiericlla resembles Strongylognatlms tcstaccus 

 in having the posterior border of the head deeply excised and its 

 posterior corners projecting as blunt horns. Santschi's interesting 

 observations have been published by Forel (1906^) and may be 

 briefly summarized. Although both sexes have well-developed wings, 

 mating seems to take place, at least as a rule, in the outer galleries 

 of the nest and between brothers and sisters (adelphogamy). After 

 fecundation the dealated female roams about over the surface of 



