140 BRITISH BIRDS. [vol. x. 



Some of those present at tlie dinner were disposed to doubt 

 the possibility of these eggs being the product of the same 

 female ; but as I am strongly of the opinion that this was 

 the case. I think it might be of interest to some of the readers 

 of British Birds to hear some further details. 



The eggs of the Nightjar as a rule show remarkable variety 

 as between clutch and clutch ; but these four eggs are 

 curiously even in shape, size, and coloration. Again it is 

 utterly improbable to my mind, that a Nightjar for no reason 

 at all should elect to lay in a nest already occupied : and 

 almost equally unlikely that if the first female came to grief, 

 the male bird would bring his second mate to a nest already 

 containing two eggs, or that she would lay therein. 



Apart from these reflections, however, I was anxious to 

 have a careful comparison made between my eggs, and a 

 larger series than I am able to boast of in my small collection. 

 I accordingly requested Mr. P. F. Bmiyard to examine them 

 for me, and to compare them with his series of Nightjars' 

 eggs (probably one of the finest series in Europe). 



Mr. Bunyard kindly undertook to do this, and I was gratified 

 to find that his opinion coincided with my own. His observa- 

 tions seem to make it quite clear that these eggs are a genuine 

 " four " from the same female, and the following quotations 

 from his subsequent letter to me, will show the grounds on 

 which his opinion is based. Mr. Bunyard says, " The eggs 

 have now had time to dry out, and after very carefully com- 

 paring them with my series, I have not the slightest hesitation 

 in saying they are from the same bird. Numbering the 

 eggs 1, 2, 3, and 4, numbers 1, 2, and .3, are of exactly the 

 same type. Number 3 is perceptibly different in shape to 

 numbers I and 2 ; the ground colour is, however, identical, 

 as is also the colour of surface and underlying pigment. 

 Number 4 is somewhat smaller. This is quite a common 

 case in clutches of two Nightjar, and is probably the last 

 egg laid. The evidence is strongly in favour of this with egg 

 number 4, as the pigment is less dense, and there is also less 

 gloss {i.e. less of the outermost glutinous layer). There is 

 also a penumbra to the surface markings, pointing to gradual 

 loss of pigment.- As regards the state of incubation, though 

 the eggs arrived partly blown, there was sufiicient evidence 

 left to enable me to form an opinion that the four eggs were 

 in two stages of incubation : numbers 1 and 2 behig four or 

 five days in advance of the others." 



In conclusion, I may add that double clutches of eggs are 

 by no means unknown, though a case has not, I believe, 

 been previously recorded in the Nightjar. In some of the 



