DEGRADATION OF STRONGYLOGNATHUS, 85 
slavery, but how they procure the slaves is still a 
mystery. They fight in the same manner as Polyergus; 
but yet Schenk, Von Hagens, and Forel all agree that 
they are no match for the Tetramoriwms, a courageous 
species, and one which lives in lurge communities. On 
one occasion Forel brought a nest of Tetramorium 
and put it down very near one of Strongylogna- 
thus testaceus with Tetramoriwm slaves. A battle at 
once commenced between the two communities. The 
Strongylognathus rushed boldly to the fight, but, 
though their side won the day, this was mainly due 
to the slaves. The Strongylognathus themselves were 
almost all killed ; and though the energy of their attack 
seemed at first to disconcert their opponents, Forel 
assures us that they did not succeed in killing even a 
single Tetramortwm. In fact, as Forel graphically 
observes, Strongylognathus is ‘une triste caricature’ 
of Polyergus, and it seems almost impossible that by 
themselves they could successfully attack a nest of 
Tetramorium. Moreover, in Strongylognathus, the 
workers are comparatively few. Nevertheless, they ure 
always found with the Tetramoriums, and in these 
mixed nests there are no males or females of Tetra- 
moriwm, but only those of Strongylognathus. Again, 
the whole work of the nest is done by the slaves, 
though Strongylognathus has not, like Polyergus, 
entirely lost the power of feeding itself. 
But if the economy of Strongylognathus is an 
enigma, that of Anergates is still more mysterious. 
