74 Mr. E. Gibson on the Ornltholoyy of [Ibis, 



Whenever a moment's respite was gained it skimmed along 

 the surface of the water for about twenty yards with a third 

 of its bill immersed; then rose^ circled onee or twice, and 

 repeated the surface-glide. For a long time, fascinated, I 

 watched the dexterous and impeiceptible use of wings and 

 tail, the reflection of the bird in the calm sunset-tinted pool, 

 and the tiny furrow ploughed by its bill. And it was almost 

 dark when I rode away and left the Skimmer and its shadow 

 still coming and going in the dusk. 



I have taken a fish, two and a half inches long, out of the 

 crop of one of these birds ; but I have never actually been 

 close enough to detect any movement or closing of the 

 mandibles, nothing but the lower one cutting its " lonely 

 furiow." 



The note is loud and harsh, but not uttered whilst fishing, 

 only when rising from the surface of the water, or if a 

 flock is disturbed whilst resting on the bank of a laguna. 



412. Sterna maxima Bodd. Great Tern. 



Iris very dark brown ; bill orange ; legs and feet black. 



Hudson evidently never met with the Great Tern. And 

 if (as he states) it occurs on the Rio Parana, according 

 to Azara, it so happens that Claude Grant did not meet with 

 it there, along with other species of Terns. The last-named, 

 however, places it to the credit of Ajo as follows : — " During 

 the week including the 1st of March (1910) several of these 

 Terns were seen, sometimes singly and sometimes in pairs, 

 passing along the Atlantic coast, but generally very far out 

 at sea. I had not met with- this species in the Ajo district 

 before. It has a very clear, shrill cry, which cannot be 

 mistaken." 



It is curious that my one and only encounter with this 

 species should have taken place about the same date 

 (13th March) of 1905. and under similar circumstances. 

 Happening to be down at Gape San Antonio, I noticed 

 a flock of between ten and twenty resting on a sand- 

 hank in company with some Gulls and Trudeau's Terns ; 

 and had just time to disengage my gun and cartridges from 



