In audition to the behaviour chart cters the Roset te reseuholes 
the Sandwich in^fcoma morpshological features too. The youn* huv« the 
ch 1 4^^ ni< 
aO-’Wo'j Uull; 
spinous" go* n'* so 'unlike the Coupon ana Arctic ano the juvenile plumage 
is also like the Sanawich but cuite unlike the other two* The outer 
web of the tc il is aslo like the Sandwich ana unlike the others in 
be in. white. 
t inry oe no co~ incidence that tue c .rey ox 
Oc c k ana 
wings of the Rose? te is the very ale grey oi the Sandwich anu not the 
darker shade of the >rs, 
Unfortunately I do not know whether anyone kno s nuca aoout the 
system? tics of Sterna- . Do you ha open to know anyone in the 6 t tie s who 
would be worth consulting ? ’.'.hen i caiae back through Amsterdam 1 
met Voous anc jiu sole to ask him aoout a few of these things out 
there was no opportunity f or e proper talk. he wt s oj. the opinion 
that one could sepax; te of l the h. xy e r, crest ea’ Tlx las^eus" type from 
the typical Sterna out felt that the Roseate should oe x» separated- 
fiom Incidentiily he t no ugh. that Hyo.ro progne might well 
be put in with Tha lasseus , a view which had suggested itseli oeiore 
r e» m m iswi— i » m nm w 
to me from Bergman 1 & paper t na which was reinforce, twentfolu when 1 
saw^er.^jan-' s film. The Sandwich tern people at the gull coniernece 
f ell^Cm: T®with the exception oi one small part oi the behaviour, the 
first hase of the Piechbeugung, the behaviour ox their sp. a mu the Caspian 
were identical. The only ity wt s that Bergman himself wasn’ t able to 
say whet he though, of the Sandwich tern film to see whether the view 
w; s mutual* 
to much for the comparison of the 4 sop. 1 could watch. There 
is another point which might interest you concerning the movement 
which accompanies the j?ish call (the loud"koreet w ) ox the Sandwich. 
When uttered by i bird on tns .ground the oira m 8 & more or less 
di inct head t. movement as it makes the call. Apart from the 
movent itself I do net knov. that there is any reason to ecuate the 
moveme nt with the head tossin oi food begging. It may be end often is 
uttered by a biro carrying a fish. 1 have seen signs that the heed tossing 
with kcrevt can graae into normal xooo oe, ...... ing, for ex n . le v hex* a brooding 
female cal as to her mete when he brings a fish for her ant eventually 
begs when she alight s at her side. 
from whet 
i saw on the film ana 
similar movo.e nt at 
from Bergman’s paper the Caspian tern also has a 
the end of its Tischbeugung which resmoles the lead tossing of a food 
be ing biro.. Lo k at photos 5,7 en.d 10 in his paper. The movements 
seem (to me) to be homologous in these two sop. but 1 would aouot their 
relation to food beg, ing, or indeed their origin from food begging 
were it not for the occurrence of a similar hesu-toosing-like mo ament 
at the end of the long Call Display in the laughing bull and also, as 
Hi . s 1 remember, .in some ox the spp. you have lo-.keu at. 1 roctlf 
tilt t i iko violently rejects the id ea of the last pha^e of tn 
Gull’s trumpeting as having anything to do with food begging 
you not hz ve so more arguments Xur thi 
I would be glau to 
•erring 
GO 
het r of 
any new iceas which ,ou might have to explain the occurrence of this 
mover, ent in this context. Perhaps it might help for the terns. 
