23 
Perhaps this second peculiarity can be linked with the bright 
inside of the mouth, lust a a the open- mouthed choking of the 
Kit tl wake, an unusual feature for a gull, may be connected with 
the brilliant mouth colour of which use is made In other dia lays. 
The beak -hiding behaviour of the Black Noddy 
h?s been compared with that of the Kittiwake* Though the gulls and 
gore of the terns have rudimentary, and some ti -os ritualised, forms 
cf the . turning tivsay, it ha- only boon developed so elaborately 
,'o ; ■ "el trie i r V* Tj r 1 be. Bln** the Klttiwake is certain- 
ly not more close' y related to the Noddies then to the ground- 
re- -'tine: nn le . th'3 b beak-hiding mu at bo regarded as an adaptive 
convergence . 
Othfcb pos tures and cells of the Blaok Noe 
the clucking. 
■ 1 . H '• *" 1 , * 
p tr v&v a t g 0 ry. y related to displays of other La rids but 
one would need evidence from more intermediate species to 
subs t Ltii t* j&rtleular relationships • 
-TL <6+L*v£<m I tk. 6*k* h)od*U U, St A M*tW* sffc-S , «* 
5 . 
f £h '.T i n ■ ary 
fir-' hf, ,1 ta 
*,' * < 1 •. i . ncu-.miTtJ h a ' ve Irrm wrl fr 
a 
r^,v', '"'T. i f -- 7v> v.-y-i * q nb M nr. a '■’lie'-- na-ti.. .sm ff 1 r» * or> , t 
•f de iuiled comparison 
bt?E SsteXKtaas with the Hack Noddy. 
In vi of this the few observations I couiu make on the displays 
of etolidus nesting around Ascension will be reported. 
There is a g spin# display identical with the Bl&ck 
Noddy 11 £ c?nci it is perTortiii^d in identical tuitions • whsn Inn 
til one # l&ndi n ■*■■; *1 * -j 1 1 v atts tetPUl#^ 
r 1 s b bright than the Black Noddy * G* 
