prisoners reach and incite them to attempt their deliverance. Many social species are thus powerfully affected by cries of distress from one of their fellows; and some will attempt a rescue in the face of great danger--the weasel and the peccary for example. Mild and sociable as the vizcachas are towards each other, each one is exceedingly jealous of any intrusion into his particular burrow, and indeed always resents such a breach of discipline with the utmost fury. Several individuals may reside in the compartments of the same burrow; but beyond themselves not even their next-door neighbour is permitted to enter; their hospitality ends where it begins, at the entrance. It is difficult to compel a vizcacha to enter a burrow not his own; even when hotly pursued by dogs they often refuse to do so. When driven into one, the instant their enemies retire a little space they rush out of it, as if they thought the hiding-place but little less dangerous than the open plain. I have frequently seen vizcachas, chased into the wrong burrows, summarily ejected by those inside: and sometimes they make their escape only after being well bitten for their offence. I have now stated the most interesting facts I have collected concerning the vizcacha: when others rewrite its history they doubtless will, according to the opportunities of observation they enjoy, be able to make some additions to it, but probably none of great consequence. I have observed this species in Patagonia and Buenos Ayres only; and as I have found that its habits are considerably modified by circumstances in the different localities where I have met with it, I am sure that other variations will occur in the more distant regions, where the conditions vary. The most remarkable thing to be said about the vizcacha is, that although regarded by Mr. Waterhouse, and others who have studied its affinities, as one of the lowest of the rodents, exhibiting strong Marsupial characters, the living animal appears to be more intelligent than other rodents, not of South America only, but also of those of a higher type in other continents. A parallel case is, perhaps, to be found in the hairy armadillo, an extremely versatile and intelligent animal, although only an edentate. And among birds the ypecaha--a large La Plata rail--might also be mentioned as an example of what ought not to be; for it is a bold and intelligent bird, more than a match for the fowl, both in courage and in cunning; and yet it is one of the family which Professor Parker--from the point of view of the anatomist--characterizes as a "feeble-minded, cowardly group." CHAPTER XXI. THE DYING HUANACO.