Read it through once

Over the Pampas used to roam thousands of guanacos (a creature of the most unlovely type, which resembles both a camel, a mule, a deer, and a horse); here also were Darwin's ostriches (_Rhea Darwinii_) and other game, which were caught by the lasso and by the peculiar "bolas" of the Indians. They used to surround the herds and then massacre them by hundreds. The "tuco tuco" also, which is a burrowing rodent with habits very like those of the prairie dog, finds plenty of sustenance in the abundant grasses. Upon them subsist pumas, foxes, and other carnivores.