Smith. — On Neio Zealand Ants. 475 



beneath the boulders as forming au economic basis for the 

 origin of the ants' nests. The cool damp undersides of the 

 boulders naturally draw the roots of plants and attract their 

 parasites to them, while at the same time they afford the 

 requisite conditions for establishing young communities of the 

 ants. The latter instinctively search for these sites, and 

 w^hile thus engaged several of the sexes meet and associate 

 together to form new nests. Beneath some of the stones we 

 have often observed where they had only commenced to 

 excavate their galleries, and we have seen others in course 

 of progress — from the most rudimentary to the highly-finished 

 and numerous galleries in the nests of the old and flourishing 

 communities. When the work of excavating the galleries has 

 commenced the ants do not readily desert the site, and they 

 bestow great care on the domestic or economic inhabitants of 

 their nests." These remarks applied chiefly to M. nitidum ; 

 and, although I mention having examined two nests situated 

 in rough shingle which contained no Coccids, they are, as a 

 rule, applicable to the origin of the nests of this species. We 

 have counted eighty-four Coccids (B . formicicola) with a single 

 colony, and probably we missed many more when digging up 

 the shingly site of the nest. After a patient search for several 

 years among hundreds of nests we have not discovered this 

 peculiar Coccid elsewhere than in ants' nests. The curious 

 beetle Diarthrocera formiciphila, Broun, we observed in tlie 

 imago state associating with ants. 



Professor E. Moniez has lately described and figured an 

 Acarian [Leiosoma longipiUis) and two Thysanura {Drepavtira 

 hrachycephala and Lipura incerta) found associating with 

 Monomoria in New Zealand. Two more species {Entomohrjja 

 multifasciata, TuUb., and Achoratis armatus, Nic, Tullb.) were 

 also among the insects sent to Professor Moniez. These latter 

 species he considers occur accidentally in ants' nests. 



M. s^tteri, Forel, is a somewhat smaller ant than M. nitidum, 

 but of very similar habits. Large and small communities of 

 this glossy-black species exist under boulders on the Ashburton 

 Eiver-bed. Like the preceding species, they haunt and protect 

 colonies of Coccids parasitic on the roots of several plants. 

 B. formicicola occurs abundantly in their nests, the white, 

 cottony fringes of this minute Coccid rendering it a con- 

 spicuous object among the bustling ants. Although D. poce 

 is commonly found on the roots of several species of Pon, it 

 attacks the I'oots of other plants, and occurs plentifully on 

 roots under stones in nests of this ant. I have seen the adult 

 females walking leisurely about the courts of the nest, where 

 there were no roots near, each covered with masses of a white 

 cottony substance. Twice have I noticed the little black ants 

 struggling ineffectually to cai*ry off some of these large Coccids. 



