83 
THE NIDIFICATION OF CERTAIN TERNS. 
By W. J. F. WILLraMsov, F. Z. S., M. B. 0. U. 
I recorded in Vol. II of this Journal (p. 63) that I had obtained 
the eggs of Sterna bergit (the Large Crested Tern), S. melanauchen 
(the Black-naped Tern), and S. ancestheta (the Panayan Tern ) on 
some islets in the Inner Gulf of Siam in June and July 1916. Nearly 
all of these, however, were procured by my collector in the first- 
named month, and he kept no record of the number of eggs in each 
clutch. By the time I was able to visit the locality, in the middle of 
July, the laying season was over, and only a few addled eggs and some 
chicks remained, so I was not in a position to repair the deficiency. 
During 1917 and 1918, I made a point of visiting these islets 
again, as well as some others, and it may be of interest to record the 
results. The dates of my visit were:—2nd June, in the former year, 
and 9th May, in the latter. 
STERNA BERGII (subsp.? ). The Large Crested Tern. 
In 1917 I obtained 9 eggs of 9. bergii, laid singly on the bare 
shingle of a beach at one end of a small islet, near Koh Rin—not the 
slightest attempt having been made by the birds to scrape out any sort 
of a depression or hollow to receive the eggs. In this respect my ex- 
perience agrees with that of Colonel Butler, quoted in Hume’s “ Nests 
and Eggs of Indian Birds” (2nd Edition, Oates (1890), p. 297). 
Despite their large size, and the promiscuous way in which they were 
laid, these eggs required to be carefully looked for, as their colouration 
and markings (varying from a dead to a creamy white, with spots, 
blotches and streaks of reddish brown to dark brown) exactly matched 
‘those of the white streaky pebbles on which they were laid. Asa 
consequence of this, one or two eggs were, unfortunately, trodden on 
inadvertently. All those obtained were perfectly fresh. 
In 1918 I collected 23 single eggs and 2 pairs on a perfectly 
bare, low-lying rock near Koh Chuan, some little distance further 
south than Koh Rin. I have already alluded to this islet (antea, 
p. 28), in connection with the record of Anous stolidus (the Noddy) 
from Siam. 
The ground-colour of a number of the eggs taken in 1918 was 
a very pale greenish blue; but this tint fades gradually to a dead 
white. 
VOL. III, NO. II, 1918, 
