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BOSCHAS 
antics. Then we must also include fighting between males as another activity of 
courtship. The word display will therefore be used in a restricted sense in describ- 
ing those social plays which result finally in the choice of a mate ; and where display 
is well developed it is probable that the female does actually select her own mate. 
But display in birds must not be confused with similar but intentional activities in 
man, for it is exercised in an unconscious manner and without real understanding. 
The word courtship has an anthropomorphic sound, and seems to imply a conscious 
and previously planned series of events, but it should not be considered in this sense 
when applied to behavior in animals. It would perhaps be better to invent an 
entirely new word to cover the long series of events which result from the “ mating 
hunger” of animals in general. 
The display of the Mallard, which is very characteristic, was first described by 
Naumann. Later writers such as Millais (1902), Heinroth (1911), Wormald (1914), 
Brock (1914), and C. W. Townsend (1916) have analyzed this phenomenon in detail. 
As has been indicated above, the display is seen at its best in the early spring, but it 
has no direct connection with the mating act, and may be seen at almost any time of 
the year when the birds are in a playful mood. According to Brock it is not seen in 
truly paired birds. As analyzed by Wormald the various positions of the male during 
display are as follows: (1) the drake floats idly on the water or swims restlessly to 
and fro in a constrained attitude, with the neck retracted, so that the head is sunk 
closely between the shoulders; (2) he raises himself abruptly in the water, at the 
same time lowering his bill to the surface and then passing it rapidly up the breast 
accompanying this action by a note, part whistle, part groan; (3) the fore part of 
the body is depressed in the water, while the tail is raised, and the bill simultaneously 
opened to the utterance of a series of short notes; (4) a simultaneous upward throw 
of head and tail, usually immediately followed by the performer (5) swimming 
rapidly to and fro in various directions, with the head and neck outstretched 
horizontally just above the surface of the water; (6) (added by Brock) the fore part 
of the body is raised rather slowly out of the water, and the head and neck are ex- 
tended upward at an abrupt angle. A characteristic head-shake frequently precedes 
this action. (See Plate 20.) 
The order above indicated is by no means always followed. In fact Brock con- 
siders 1, 6, 3, 4, 5, the more usual sequence. The display in the female is far less 
developed, but she often performs as in (5) and in doing so stimulates the male to 
respond by actions 2, 3, 4 and 5, particularly the last two. Such display is at first of 
a general nature, and may not have any reference to individuals of the opposite sex; 
in other words, as Brock says, they are merely the outward expression of certain 
forms of nervous stimuli. Nevertheless the attraction or stimulus which a female 
exerts is in direct relation to her exhibition of display primitive as it appears, and is 
inverse to her passivity of behavior. 
