183 
Mr. Uuller calls attention to the fact that whereas all the species 
which nest in hollow trees, or other .situations accessible to the 
L'at, are decreasing in number, those which build suspended nests 
show no decrease. One species, however, the New Zealand Eock 
Pipit, which builds on the ground in open grass land, and might 
tlioreforo be suppo.sed to bo peculiarly liable to the depredations°of 
the Puits, IS oven on tlio increase; this is due to the compensating 
influence of the Harriers, which prey upon the rats and preveiit 
their undue increase wliere they lack the protection of the cover. 
l>ut it is iiot only the pests which accompany man, much 
against his will, but also animals in themselves most useful, that 
assist greatly in the work of destruction. Our early navigators, 
actuated by the best motives, and thoughtful only of tho.se who 
might follow, freciuently liberated Pigs and Goats in the countries 
where their ves.sels stopped ; these soon became feral, and over- 
spread the country Avith the most disastrous results. There seems 
to be no doubt that to this cause must be attributed the final 
destruction of the Dodo of the Mauritius ; perhaps, also, of its 
white cousin of lieunion, of which not even a bone is known to 
remain, as well as of the Solitaire of Rodriguez; and who can tell 
how many other members of the remarkable Avi-fauna of the 
Mascarine group, the greater portion of which was incapable of 
flight. No indigenous terre.strial mammalia existed on the 
islands, and we can readily imagine the swine turned loose by the 
earliest visitors, revelling in the abundance of eggs and youn" of 
the helpless and inert ground-breeding birds, new to the experience 
of such depredators. In a paper on the “Osteology of the 
Solitaire, by A. and L. Ncivton (Phil. Trans. 1868, p. 327, &c.), the 
authors, after stating that in nearly all the cases in which animals 
lave become extinct through the agency of man, it will be found 
w len the history of the extinction is sufficiently knoAvn, that the 
result was brought about less by his direct than by his indirect 
agency, continue: “Rut with the Solitaire of Rodriguez, as Avith 
the I odo and many other animals, it seems to us that there is no 
good ground for believing tliat they AArere pursued to the death of 
the race by man. It is fiir more likely that they succumbed to 
other forces set in motion indeed by him, but without a thoimht of 
thereby accomplishing their destruction. It does not seem°at all 
unreasonable to suppose that either or both might have survived 
