THE PONEKINE ANTS. 2 43 



developed receptaculum seminis. The number of ovarian tubules is the 

 same as in the workers, which also occasionally possess a receptaculum. 

 Of course, there can be no nuptial flight, and the gynsecoicls must be fer- 

 tilized either by the males of their own or other colonies, and either 

 in the nest or while traveling over the ground. 



That the same peculiar usurpation of the queen function by 

 gymecoid workers obtains among other species of Leptogcnys is indi- 

 cated, first, by the fact that winged Leptogcnys females have never been 

 seen, although the genus is a very large one and widely distributed 

 through the tropics of both hemispheres, and second by Wroughton's 

 observations on the Indian L. diminnta (Forel, 1900- '03). At Forel's 

 request Wroughton carefully excavated an enormous formicary of this 

 species, "but looked in vain for a female among the many thousands of 

 workers. All he could find was a worker whose abdomen was con- 

 spicuously distended with the ovaries. This worker differed in abso- 

 lutely no particular from the others, and there was nothing very extra- 

 ordinary even about its abdomen." It is probable that several other 

 Poncrinc genera are in the same condition, for example the paleotrop- 

 ical Diacainina and Champ somyrmex, of which the winged females 

 have never been seen. Wasmann (19040) has recently shown that even 

 in the highly specialized genera Formica and Polyergns single gynae- 

 coid workers may assume the role of queens that have been removed 

 from the colony. It seems probable, therefore, that the Ponerinse 

 above mentioned present a degenerate, or, at any rate, secondary 

 stage of colonial development in which the true female form has dis- 

 appeared and is supplanted by a worker, elected, so to speak, to the 

 reproductive office. If this be true, we may be able, as I shall endeavor 

 to show in the next chapter, to account for the peculiar dichthadiiform 

 females of the Dorylinse. 



The habits of the Ponerin?e reviewed in the preceding paragraphs 

 present a mingling of primitive and specialized features, both very 

 interesting, the former because they throw light on the more intricate 

 ethological conditions in the higher ants, the latter because they suggest 

 the enormous antiquity of certain formicine instincts, which must have 

 persisted with little change since Mesozoic or early Tertiary times. 

 Several peculiarities, such as the highly entomophagous habits of the 

 adults, the feeding of the larvse with pieces of insect food, the retention 

 of the cocoon, the ability of the callows to hatch unaided, the small size 

 of the colonies and the slight fecundity of the females in many species, 

 coupled with many morphological characters, leave little doubt that the 

 Ponerinse arose from solitary wasps. Emery, who has studied this 

 subject (1895), believes that the immediate ancestors of the ants are 



