46 



DISCOVERY 



little forward ; and the neck, presumably so as not to 

 throw the centre of gravity further up, is bent down in 

 an ugly curve half-way to the groimd. The bird only 

 saves itself from falling forwards by moving, and 

 can only do so, as I said, for a short time. 



On reaching the nest, she almost always, while still 

 standing, carefully presses the two eggs well into her 

 feathers with her beak, then sitting down and rolling 

 from side to side to get them comfortable. After a few 

 minutes she will usually rise and rearrange the eggs. 



I was watching the nest with one egg, referred to 

 above, with a telescope, from a hiding-tent some forty 

 yards away. The hen had been sitting steadily for 

 several hours, protecting the egg from marauding skuas 

 and gulls. Suddenly her mate flew down onto the 



A REM.\RK.\BI,Y IE.\RI.ESS DI\ liR SNAPPING AT A;, i; . ij. LHai 

 (THE WRITER). 



pool. Almost at once she left the nest, made towards 

 the cock, and swam round him several times with her 

 neck extended in front of her — a snake-like pose, but 

 one rigid with excitement. However, he was un- 

 responsive. Soon after, she gave what I call the 

 "splash-dive." The bird dives with a flick, sending 

 a shower of spray into the air (as opposed to the 

 noiseless submergence of serious diving for food), to 

 emerge only a few feet away, alwa^^s close to its mate. 

 This was repeated four or five times, and stimulated 

 the cock to a little similar diving. I have since found 

 that this splash-diving is always associated with 

 excitement (sometimes with quite other forms of 

 excitement, as when one very tame bird employed it 

 in anger when I drove her off her nearly-hatching eggs), 

 and seems to be especially used as a stimulus by one 



bird of the pair — it may be either male or female — to 

 key up the emotions of the other. Immediately after- 

 wards they swam together to a low bank of green moss, 

 onto which the cock scrambled. He stood upright, 

 stamped alternately with his feet, and sank down to 

 rest. I found later that he was sitting on a rudiment- 

 ary nest, a " cock's nest," such as also is built by the 

 Crested Grebes ; and found a similar cock's nest on 

 the other nesting-pool that I was able to investigate 

 thoroughly. 



The cocSv picked at the moss, and seemed to be 

 building pieces of it into the " nest." The hen mean- 

 while, although the water was scarcely deeper than 

 herself, was giving splash-dives over and over again. 

 On a subsequent visit to the same place she occupied 

 herself in ducking under, pulling up great pieces of 

 moss from the bottom, throwing them aimlessly over 

 her shoulder, and repeating the process. 



From what I afterwards saw, it became clear that 

 each pair had a special place, like this moss-bank, 

 where there was a cock's nest and where the act of 

 pairing always took place — a nuptial bower. 



Two points deserve special notice. First that in 

 other species where such special pairing places are 

 found, they usually contain a rudimentary nest ; for 

 instance, in the Crested Grebe. This bears out 

 Selous' contention that the whole se.xual life of the 

 birds originally centred round the nest, and that now 

 we see a " division of labour " between the two func- 

 tions of the nest — the incubatory in the true nest, the 

 nuptial in the rudimentary nest by the pairing-place. 



Secondly, and in a way arising out of the first, we 

 have the strong association between nest-material and 

 the emotion of love. This association is by no means 

 confined to species which have special pairing-places. 

 To choose but three examples, not only does the grebe 

 have elaborate ceremonies in which bunches of weed 

 dived for from the lake-bottom play a prominent part, 

 but herons and egrets present each other with twigs 

 to an excited ceremonial accompaniment, and the 

 mates of warblers often make their displays before the 

 hens with a leaf or twig held in their beak. Mental 

 association, in fact — and this is an important general 

 conclusion — plays a large part in building up the com- 

 plicated courtships of birds, and so presumably in their 

 whole mental life. 



The mate of this particular pair of mine shortly flew 

 off, but returned again later in the day. This time, 

 the typical ceremony of the Diver's married life was 

 gone through. After some preliminary' diving, the 

 two birds both put themselves into the characteristic 

 position. The neck was arched right forward, the 

 head bent down ; the beak was open, and its lower 

 third or half was submerged in the water. From both 

 birds issued an extraordinary cry, which in my notes 



