OCCASIONAL NOTES. 293 
readily distinguished from that animal by the shortness and roundness of 
the ears and comparative shortness of the tail. I do not know that it has 
been previously observed, but I see that, in swimming, Mus decumanus uses 
its tail, not in the manner of a man sculling a boat from the stern, but with 
a horizontal snake-like motion Ww. Borrer (Cowfold, Horsham). 
PurPLE GALLINULE IN SomERsersHinE.—The Somersetshire Purple 
Galliule seems to raise rather an interesting question—namely, what 
amount of evidence should be required to admit a bird confessedly killed in 
an apparently wild state within the British Islands to a place in our list of 
birds as a bond fide wanderer. I quite agree to one of the remarks made by 
Mr. Mathew in the June number of ‘ The Zoologist’ (p. 252), that “it is 
well nigh impossible to lay down any hard and fast rule;” each case must 
be decided on its own merits. But Mr. Mathew immediately after seems to 
suggest, in spite of the difficulty of doing so, that we should draw a hard 
and fast line line at “a Parrakeet, a Whidah Bird, or a Canary in its yellow 
plumage.” If this is to be done, and we are to admit everything else merely 
on evidence of its having been found in an apparently wild state, and with 
no signs of having been in confinement about it, we should—in these days 
when the taste for keeping birds in confinement is so prevalent—have to 
increase the British list indefinitely. There are, besides the mere signs of 
captivity, many things which we ought to consider before admitting a sup- 
posed wandever into the British list. For instance, the habitat, whether 
near to these islands or distant—if distant, had the bird been found at any 
intermediate places ; how separated, by land or water, whether confined to 
a small spot or extending over a considerable geographical area; the habits 
and capabilities of the bird—whether of a wandering nature and possessed 
of considerable powers of flight—whether migratory, and if so, within what 
limits—whether, either at its breeding stations or on the journey to or fro 
it is likely to fall in with flocks of birds bound to these Islands with which it 
might associate—what the line of migration might be, whether along a coast- 
line from which, if blown by a gale or wandering in foggy weather, it would 
probably reach these shores as the first land. Food also may be taken into 
consideration, as there are some birds which, from the nature of their food 
as well as from their habits, it is quite impossible to keep in confinement, 
and therefore they could not be brought to these Islands from any distance 
by the help of man; others, however, are very easily tamed and fed, conse- 
quently may easily be brought any distance with very little care and 
attention, and would show little or no signs of confinement on their arrival 
here. On the ground of food alone, there are many birds which we should 
be disposed at once to admit as bond fide wanderers, on satisfactory evidence 
of their having been found here in an apparently wild state. Such, for 
instance, would be the Alpine Swift, Bonaparte’s Sandpiper, and the 
American Little Stint. As an illustration of some of the foregoing remarks, 
