MANX PETREL. 
187 
diving in pursuit of sprats, anchovies, the sepiadae, and 
other marine productions. It is very amusing to watch a 
flock of these Petrels thus employed : the birds are seen 
swimming on the waves, with their heads in the water, 
all in the same direction, and moving on very rapidly, the 
hindermost bird always flying up and settling in advance of 
the foremost, like rooks following a plough. Fishermen, 
when in pursuit of their calling, watch carefully the move¬ 
ments of these birds, and, when they see them thus em¬ 
ployed, lower their nets with a tolerable certainty of flnding 
the shoals, of which they are in search, near the surface. 
The flight of this species is very quick, and almost always 
pursued close above the surface of the waves, which neces¬ 
sarily requires great agility in order to escape being over¬ 
taken by the undulations of the surface; the diving is per¬ 
formed by shooting head foremost under water, in pursuit of 
the prey that comes near its surface, but never by striking 
the flsh from above, while in the act of flying. 
In consequence of the formation of the legs and feet, 
and their position, this bird is incapable of walking, or stand¬ 
ing for any length of time on the ground, or showing itself 
off* to any advantage. 
During the breeding-season the Manx Petrel comes to 
the rocky coast, and chooses the loftiest shelves, or the 
very tops of the rocks that are covered with verdure ; in the 
earth or sand of which, the bird makes a hole of about two 
feet in depth, like the hole of a rabbit, and at its further 
extremity the female deposits a single egg, of size and 
colour as represented in our plate. It seems as if the digging 
of the hole for the nest is a work of labour and time, as the 
birds may be seen to work at it for some weeks before an 
egg is found, which need not be sought for before the 
middle of June. The male and female incubate the efftr 
