382 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1921. 



acacias "have no more need for their ants than clogs for their 



fleas." x 



The first writer to call attention to the remarkable relationship 

 between the ants and the acacias was Francisco Hernandez, the dis- 

 tinguished protomedico of Philip II, sent by his sovereign in 1570 

 to study the resources of New Spain. In the Huasteca region of 

 northeastern Mexico he came upon a thorny tree, called by the Aztecs 

 Iloitzmamaxalli, or "Forked thorn," which he described under the 

 Latin heading Arbor cornigera, " Horn-bearing tree," as follows : 



The Hoitzmaruaxalli is a tree 

 with leaves resembling those of 

 a mezquite or tamarind, yellow 

 flowers, edible pods, and horns 

 very like those of a bull, growing 

 on the tree's trunk and branches. 

 The leaves, which apparently 

 have no savor when tasted, are 

 reputed to be an antidote for 

 poisons. Pounded to a paste 

 and applied to the bites of ser- 

 pents and other venomous ani- 

 mals, the wounds beforehand 

 having been scarified, they are 

 said, within a space of six hours 

 more or less, to counteract and 

 extract all the venom, in the 

 meantime assuming a black 

 color. Moreover, within the 

 horns there are generated cer- 

 tain slender ants, tawny-colored 

 and blackish, whose sting is 

 hurtful, causing pain which 

 persists for a whole day. The 

 eggs of these ants, wormlike in 

 form, reduced to a powder and 

 inserted into the ears, likewise 

 distilling into them the juice of 

 the leaves, allays earache; and 

 the juice will also cure tooth- 

 ache. This plant grows in the 

 warm region of the Huaxteca in localities near the Gulf coast both flat and 

 hilly. 2 



On plate 3 is shown a pair of these hollowed hornlike spines, with 

 the ants, larvae, pupae, and eggs which were taken from it. 



The above description, written in Latin about the year 1575, but 

 not published until after the death of Hernandez, was accompanied 



1 See Wheeler, W. M. Observations on the Central American Acacia Ants, in Trans. 

 Second Entomological Congress, pp. 110-139. 1912. 



2 Hernandez, Francisco. Prodromus, p. 48. 1651. 



Fig. 1. — Branch of Hoitzmamaxalli. {Acacia her- 

 nandczii Safford) with " horns very much like 

 those of a bull." Figured by Hernandez from 

 a specimen growing in the Huaxteca region of 

 Mexico (157G). 



