WHISKERED TEEN. 83 



Small Terns with slender, short bills, long wings, small legs and feet, and short 

 tails. The diagnostic features of this genus are the short tail and deeply-incised 

 webs of the feet. The metatarsus is a little less than the middle toe alone, and is 

 only about two-thirds the length of the culmen. The tail is less than half the length 

 of the wing, and is slightly forked, the lateral feathers not developed into streamers 

 but still the longest. The legs and feet are small, the tarsus shorter than the middle 

 toe ; the tarsal covering consists of horizontal scutes in front, rest of leg reticulately 

 scutellated ; the webs deeply incised, the outer less than the inner ; the inner toe 

 shorter than outer, which is less than the middle one ; hind -toe fairly long. The 

 species C. leucopareia has a more powerful bill and the webs of the feet more deeply 

 incised, and for it the genus Pdodes was provided. 



Coloration black above and below. 



59. Chlidonias leucopareia. WHISKERED TERN. 



[Sterna leucopareia Temminck, Manuel d'Orn., 2nd ed., Vol. II., p. 746, before Oct. 21st, 1820 : 



Hungary, Europe. Extra-limital.] 



Gould, Vol. VII., pi. 31 (pt. xxxiii.), Dec. 1st, 1848. Mathews, Vol. II., pt. 3,|pl. 103, Sept. 



20th, 1912. 



Hydrochelidon ftuviatilis Gould, Proc. Zool. Soc. (Lond.), 1842, p. 140, Feb. 1843 : Interior 



of New South Wales. 



Hydrochelidon lewopareia rogersi Mathews, Nov. Zool., Vol. XVIII., p. 207, Jan. 31st, 1912 : 



Parry's Creek, North-west Australia. 



DISTRIBUTION. Australia. 



Adult male. General colour pale grey including the back, wings and tail J 

 outer web of first primary dark brown, and showing scarcely any grey, the remainder 

 silvery-grey on the outer webs, darker at the tips, and on the inner webs near the 

 shafts as also the inner margins ; basal portion of inner webs white, which extends 

 in a narrow line towards the tips of the feathers ; inner primaries and secondaries 

 pale grey with white on the inner webs ; tail pale grey, the outer feathers margined 

 and tipped with white ; head and hind-neck black ; sides of face, throat, under 

 tail-coverts white, like the axillaries and under wing-coverts ; fore-neck pale grey ; 

 breast and abdomen dark slate colour, more intense on the latter ; bill dusky -red, 

 base of upper mandible black, tinged with red ; iris blackish -brown ; feet and legs 

 red. Total length 274 mm. ; culmen 31, wing 231, tail 90, tarsus 23. 



Adult female. Similar to the adult male, but paler on the upper-parts and the 

 dark slate-grey of the under parts restricted to the abdomen, the breast being similar 

 to the fore-neck. Total length, " in the flesh, 250 mm." ; culmen 28, wing 213, tail 

 70, tarsus 22. 



Adult male in winter. Differs from the adult male in breeding-plumage, in 

 having the crown of the head white with minute pear-shaped black spots, which 

 increase in size on the nape ; the ear-coverts dusky -black, and the entire under- 

 surface pure white. A male example, which we do not consider to be quite adult, 

 appears to be just assuming the breeding-plumage, and has the head black with 

 the remains of white feathers intermixed, and the dark lead -grey of the breast 

 approaching. 



Young. Differs from the adult in having the feathers of the back white, tipped 

 with dark brown and edged with ochreous-buff ; scapulars and innermost secondaries 

 dark brown edged and barred with ochreous-buff like the inner greater wing-coverts ; 

 tips of tail-feathers brown, edged with white ; head dark brown with ochreous-buff 

 tips to the feathers ; fore-head white, tinged with buff ; lores white, tipped with 

 dark brown ; an indicated band of buff on the middle of the abdomen, which appears 

 to be the remains of a younger plumage. 



Immature. Almost pure white below with only a tinge of grey on the abdomen ; 



G 2 



