THE FALKLAND ISLANDS. 



431 



faunistic relationship with western North America, but this 

 affinity seems to be confined to very ancient groups of verte- 

 brates and invertebrates. I ventured to allude to the North 

 American porcupines as being possibly the descendants of 

 Steiromys, which I suggested had utilised the early Tertiary 

 land connection from Chile to Mexico or California. Stei- 

 romys, however, is long since extinct. If we suppose the 

 coyotes to have taken advantage of that land connection in 

 early Tertiary times, we might assume a member of that early 

 fauna to have succeeded in surviving in these lonely islands 

 until recent times. But the difficulty in accepting such an 

 hypothesis is that it would give the coyotes a much longer 

 ancestry than any palaeontologist would care to admit. Never- 

 theless it is the only theory I can suggest. Another question 

 that occurs to me is If the wolf was the only mammal in- 

 habiting the Falkland islands, what did it live on ? Wolves are 

 carnivorous, as everyone knows, usually feeding on smaller 

 mammals. Yet Darwin states that it is the only quadruped 

 native to the islands ; he adds, however, in a footnote, " I have 

 reason to suspect there is also a field mouse." This is probably 

 a species of Keithrodon or some allied genus. Still this 

 mouse-like creature could scarcely have constituted the sole 

 food of such a large animal as the wolf. In all likelihood, 

 some larger rodent existed on the islands and may have 

 become extinct before the advent of man. The wolf soon after 

 this event shared the same fate. 



An examination of the earthworm fauna, which is probably 

 of very great antiquity, reveals the fact that there are living 

 on the Falkland islands two species of the genus Noteo- 

 drilus (N. bovei and N. falclandicus) which otherwise is con- 

 fined to South and Central America, New Zealand, Australia, 

 Cape of Good Hope, Madagascar and several of the antarctic 

 islands. A second genus, viz., Chilota, which is represented on 

 the Falkland islands by Chilota daleti, inhabits only southern 

 South America and the Cape of Good Hope, with the exception 

 of a single species living on the Cape Verd islands. The third 

 genus, Yagansia, has not yet been found on the Falkland 

 islands. It is almost peculiar to Chile and Argentina. Only 

 one species of Yagansia has been met with in South Africa.* 

 * Michaelsen, W., " Verbreitung d. Oligochaeten," p. 74. 



