76 Mr. E. Gibson un the Ornithology of [Ibis, 



should perch, as Gulls frequently do, is so unusual that I 

 took special note of the fact when I saw three on a wire- 

 fence in a sea of water. 



Eighteen years liad passed before I found my first breed- 

 ing-colony (in 1890), since which time I have noted only 

 other five. The periods vary from 26 October to 5 January. 

 As a rule, the Terns were associated with the Spot-winged 

 Gull [Larus maculipennis Licht.) ; two exceptions consisted of 

 small groups of three and ten pairs respectively. In the 

 other four cases the number of pairs ranged from half-a- 

 dozen up to perhaps forty, and the nests were interspersed 

 with those of the Gulls, sometimes closely situated, at 

 others widely scattered. The localities seemed capriciously 

 selected, being either of a lonely nature or one liable 

 to be molested by passers-by : a matter of caprice, in 

 short. As tlie situation was always of an open nature (a 

 large expanse of water covered by weeds and generally 

 at the side of a swamp) it was open to detection from a 

 long way off. The nest seemed to differ in construction 

 according to circumstances, but the material was always 

 soaking-wet water-weeds, and floating in a bed of the same. 

 Occasionally it would be a slovenly platform ; other colonies 

 presented a small, round, and neat type, with a more or less 

 pronounced hollow, and measuring two inches high by nine 

 across at base and four or five at top. 



The usual full clutch consists of three, but four is not 

 uncommon. The eggs are generally oval in shape, often 

 elongated, and sometimes pear-shaped ; in fact they are 

 rather irregular. In some cases the ground-colour is oliva- 

 ceous, in others brown or yellowish brown, and is spotted 

 and blotched with dark ash-grey, dark brown and black, or 

 strong dark red-brown markings and (under the suiface) 

 dull lilac spots and blotches. Each clutch presents its own 

 characteristics, whilst leaning towards one of the half-dozen 

 general types into which it is found that a large series 

 divides itself. 



The average measurement is 43 x 31 mm. That of the 

 largest clutch 44 x 31 mm,^ and the smallest 41 X 29 mm. 



