INTRODUCTION. x1 
 T. bonapartii (9), T. pusilla (2), Gallinago wilsoni (1), Macro- 
rhamphus griseus (15), Numenius borealis (4), Botaurus len- 
tiginosus (14)*, Crex carolina (1), Cygnus americanus (1), 
C. buccinator (1), Anser albatus (1), Anas americana (6), 
Clangula albeola (5 or 6), Gidemia perspicillata (10), Soma- 
teria spectabilis (15), and Mergus cucullatus (11). 
It is extremely difficult to believe that the non-aquatic 
species in this list have actually journeyed across the Atlantic, 
and performed a voyage of at least 1700 nautical miles on 
the shortest route, vid Newfoundland ; but that most of them 
have actually done so seems proved by the fact that they 
have never been met with in Greenland, Iceland, and the 
Farée Isles (the only countries through which they would 
otherwise have passed by a change of route); and many 
which have thus found their way to England or Ireland (as, 
for example, Ageleus pheniceus, Cuculus americanus, Ceryle 
alcyon, Aigialitis vociferus, Totanus solitarius, Tringa bona- 
parti, Botaurus lentiginosus, and others) have never been 
met with on any part of the European continent. As might 
be expected, at least half the American species found in this 
country belong to the orders Grallatores and Natatores, 
while of the 14 species of Insessorial birds, none of them, 
with the exception of Ageleus pheniceus, has occurred half 
a dozen times. This plainly shows that their appearance on 
this side of the Atlantic is the merest accident, and not the 
result of any continued and successful attempt at migration. 
In some instances at least it is not unreasonable to suppose 
that these small birds must have availed themselves to a 
great extent of the rigging of passing vessels, or have been 
brought to this country in cages, from which they have been 
* Jn addition to those noticed at pp. 150-152, I have recently been in- 
formed by Sir John Crewe that a specimen in his collection was killed 
at Slingsby, near Malton, Yorkshire, on the 4th Dec. 1871. 
