56 THE ZOOLOGIST. 



to the end that coition might be there effected, and this, it is 

 obvious, though suggested by peckings, is compatible with a fair 

 amount of conjugal affection and happiness. It had not, how- 

 ever, that appearance. The idea it conveyed was simply that 

 one rotating bird resented the too near approach of the other. 

 Moreover, I was unable to catch in these curious revolutions any 

 of those characteristic features with which I am acquainted in 

 the true sexual display of birds, nor did they appear to me to be 

 at all well adapted for showing off the plumage. Certainly no 

 detailed display of it was made by these movements, nor were 

 they justified by the general effect, which did not, by any means, 

 exhibit the bird to the best advantage. In fact, there seemed no 

 relation between the movements themselves and such beauty of 

 plumage as the bird possesses, and, having myself seen Dancing 

 Mice, I was at once struck with the similarity between the two 

 performances,, both seeming pathological in their origin. That 

 this irrelevant and inartistic little whirligig, however originating, 

 has now come to be a sexual antic is, I think, quite probable, 

 but I cannot believe that it has been developed along the true 

 lines of sexual selection. As will have been seen, it differs 

 entirely from anything that might be described as a circling 

 dance of one sex around the other. Possibly we see in it the 

 degeneration of such a one, but these birds, at any rate, circled 

 round nothing but their own axis, and, when tbey stopped, it was 

 difficult to think they did so for any other reason than because 

 they were giddy. The degradation of something rather than its 

 legitimate development is suggested to my mind. I timed the 

 duration of these St. Vitus-like dances on two or three occasions, 

 and found that they lasted just a minute. I am convinced that 

 they were sometimes much longer, but a minute is a good time 

 to keep spinning round like a top. I ought to have timed them 

 oftener, but it is very tedious doing so, as it is quite impossible 

 to say which is going to be a longer or shorter performance, just 

 as in counting the number of claps of the wings above its back, 

 given by the Nightjar. Perhaps, however, three times (I think 

 it was three) is sufficient to show the average length. I am 

 sorry that I have not begun to watch these birds, in a special 

 manner, earlier. They have been squeezed out, as it were, by 

 others that, perhaps, are less interesting. It would appear that. 



