1909.] LAXTERN-SLIDES OP BRITISH TERXS. 801 



result was noted in a casual walk across their nesting area on 

 July 2na, 1907:- ^,,,^;_ 



102 nests contained 1 egg each = 102 eggs 

 121 2 eo-2-s = 2A'2 



£ 55 55 " 55 55 ^= 27 ,, 



232 nests contained 371 eggs 



He had observed very considerable variation in the position 

 and surroundings of the nests. Some of these were made in long 

 grass ; some in short grass ; others on quite bare sand, and others 

 on a bank of shingle. The materials of the nests also showed 

 great variation, but generally speaking it was the exception to 

 find a bulky nest of this species. The large majority were simply 

 holes scratched in the sand or gi-ass without either structural or 

 lining material. He had noticed very considerable variation in 

 the colour of the eggs, and this applied both to the ground-colour 

 and markings. As a rule the ground-colour was much duller 

 than that of either the Sandwich or the Little Tern. 



Lesser or Little Tern (Sterna viinuta). — This was the least 

 numerous of all in the locality named — the colony including not 

 more than about half a dozen pairs. The Lesser Terns were 

 generally less social in their habits than any of the others. They 

 also nested further apart, and he never found it possible to in- 

 clude two nests in the same half-plate photograph. Moreover, 

 the Little Terns always seemed to choose a nesting area quite 

 near to the sea, or river estuary, and for the most part on a sand- 

 bank only just above high-water mark. The white crescentic 

 band on the forehead characteristic of this species was clearly 

 shown in the photographs. Most of the Lesser Terns seemed to 

 use small stones and broken fragments of shell as nest material, 

 and in this respect they were quite chai-acteristic. 



Roseate Tern {Sterna dougaUi). — The series of photographs of 

 these birds shown by the Lecturer were unique, being the only- 

 series ever taken within the British Isles. He did not give the 

 locality in which the photographs wei-e obtained, as he wished 

 to do what was possible to px'otect this rarest and perhaps most 

 beautiful species of the group. Roughly speaking there were in 

 the nesting area referred to about 10,000 pairs of Arctic Terns 

 and 1000 pairs of Common Terns. So far as he could judge, 

 there were not more than from fifteen to twenty pairs of Roseates, 

 and of these he managed to find eight distinct and clearly iden- 

 tified nests, each of which contained only one egg. From the field 

 naturalist's point of view there wei'e four marks of distinction of 

 the Roseate Tern, viz., the roseate colour of the breast, the black 

 bill reddish just at the base, the harsh cry " crrark-crrark," and 

 the long streamers of the tail. He cited Mr. H. E. Dresser's 

 statement that "the wing of this species was nine inches in length 

 and the tail nine inches in length, and that the lateial feathers of 

 the tail extended nearly six inches beyond the central ones." 



He had found that the Roseate Terns seemed to prefer 



