402 NOTES OF A BOTANIST CHAP. 



all, with the exception of the herbaceous species, 

 are infested by ants. The order is Polygonese ; 

 the ant -infested species belong to the genera 

 Triplaris, Coccoloba, Campderia, Symmeria, and 

 Rupprechtia ; and the exceptions are species of 

 Polygonum, some of them closely resembling 

 common European species. All, both trees and 

 herbs, grow in moist situations, and most of them 

 on lands subject to periodical inundations. Not 

 only is every lignescent Polygonea a habitation 

 for ants, but the whole of the medulla of every 

 plant, from the root nearly to the growing apex of 

 the ramuli, is scooped out by those insects. The 

 ants make a lodgment in the young stem of the 

 tree or shrub, and as it increases in size and puts 

 forth branch after branch, they extend their hollow 

 ways through all its ramifications. They appear 

 to belong all to a single genus, and are long and 

 slender, with a fusiform, very fine -pointed, dark- 

 colourecl, shining abdomen,- and they all sting 

 virulently. They are known in Brazil by the name 

 of " Tachi ' or " Tac^ba," and in Peru by that of 

 "Tangarana"; and in both countries the same 

 name is commonly applied to any tree they infest 

 as to the ants themselves. 



A few trees and shrubs of other orders are 

 similarly infested by Tachi ants ; such as Platy- 

 miscium (Vog.) in Leguminosse, Tachia (Aubl.) in 

 Gentianeae, and Mabea (Aubl.) in Euphorbiacese. 



Triplaris surinamensis, Camb., a Polygoneous 

 tree of very rapid growth, reaching at maturity a 

 hundred or more feet in height, and conspicuous 

 from afar when in fruit from the abundance and 

 bright red colour of its enlarged shuttlecock -like 



