SIX MONTHS BIRD COLLECTING IN EGYPT. 203 



subject appear to require further elucidation.* They do 

 not appear to have got it, as I cannot lay my hand on any 

 work which explains why two adult black-backed males, shot 

 in the spring, should have, the one a dark-brown head and 

 neck, and the other those parts white ; but it is so in two of 

 my Egyptian skins. I shot eight or nine Stilts, and I took 

 some pains to unravel the mystery of their plumage, but all 

 I could ascertain was that the black-backed ones were never 

 females, though the brown-backed ones might occasionally 

 be males. Perhaps the white head is the summer plumage.f 

 Mr. Blyth has some remarks on the colour of their heads in 

 "The Ibis" (1865, p. 35), and he concludes by saying that 

 the most likely explanation is " that differentiated races of 

 this bird have been more or less commingled." This is 

 probable, but not satisfactory. 



The skin of the leg is scurfy, and the colour varies, the 

 lightest birds having the lightest legs. The tarsus in the 

 male is longer than in the female. 



166. Collared Pratincole, Glarcola pratincola 

 (Linn.) ; " Abou El Rusr." 



Generally in flocks, but occasionally solitary. First shot 

 on the 2nd of April. All naturalists have found a difficulty 

 in saying to what family these birds belong. In their cry, 

 flight, etc., I think they more resemble Terns than any 

 other birds, and they are more often seen on a sandbank 

 than inland. Four shot on the 9th of June out of a large 

 flock had beetles in their crops with red backs and a peculiar 

 smell. Their being in a flock looked as if they were not 

 breeding. 



^ Vide Gurney and Fishei- in "Zoologist" for 1846, p. 33. 



•f Against this view I must remark that Canon Tristram has a black- 

 headed specimen, shot by himself in Algeria in June, and he informs 

 me that others killed at the same time were black-headed also. 



