182 HYMENOPTEEA. 



The genus Ponera is found distributed throughout the 

 tropics. The females and workers are armed with spines ; the 

 abdonieu is elongated, the segments more or less diminished 

 in size, the first comparatively large and often cubical. The 

 legs are slender. P. ferruginea Smith is a Mexican species. 



The allied genus OdontomacJms springs lilve some leaping 

 spiders. It uses for this purpose its unusually long mandibles, 

 which are bent at right angles. 0. dams Roger lives in Texas. 



Formica includes the typical species of ants. Over two hun- 

 dred species of this genus have been already described. The 

 body is unarmed. The abdomen is short, oval or spherical, 

 the scale-lUie first segment being lenticular in form, with a 

 sharp upper edge. The subcostal cell of the fore-wings end in 

 a point. Formica sanguinea Latr. is one of our most abundant 

 species, making hillocks of sand or claj^, according to the nature 

 of the ground. From the formicary walks, and underground 

 galleries, radiate in all directions. This species has been ob- 

 served making forays upon each others colonies. "We have 

 found a variety of this species in Labrador, where it is com- 

 mon. It does not throw up hillocks, but tunnels the earth. 



This species has been observed in Europe by P. Huber, to 

 go on slave expeditions. They attack a " uegTO-colou}- " be- 

 longing to a smaller black species, pillaging the nest, and carry- 

 ing off merely the larvie and pupse. The victors educate them 

 in their own nests, and on arriving at maturity the negroes take 

 the entire care of the colony. Pohjergus rufescens is also a slave- 

 making ant, and " Latreille ver}^ ji^istly observes that it is phj'si- 

 cally impossible for the rufescent ants {Polyergus rufescens)^ 

 on account of the form of their jaws, and the accessor^' parts of 

 their mouth, either to prepare habitations for their family, 

 to procm-e food, or to feed them." Formica sanguinea sallies 

 forth in immensely long columns to attack the negTO ant. Hu- 

 ber states that only five or six of these foraj's are made within 

 a period of a month, at other seasons thej'^ remain at peace. 

 Huber found that the slave-making Polyergus rufescens when 

 left to themselves perish from pure laziness. They are waited 

 upon and fed b}' their slaves, and when they are taken away, their 

 masters perish miserabl}'. Sometimes thej^ are known to labor, 

 and were once observed to carry their slaves to a spot chosen 



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