LAEID^i IiAEUS 423 



strong but not so long as in Sterna, reaching to about the end of the 

 tail ; first primary the longest ; tail square or nearly so ; lower 

 third of the tibia bare like the tarsus, the latter strong and usually 

 longer than the middle toe and claw with transverse scutes in 

 front ; front toes fully webbed, hind toe small and rudimentary. 



Fig. 131.— Right foot of Larus hartlaubi, from inside, x ^ 



This is a large genus containing, according to Saunders, some 

 forty-four species of Gulls, spread over the greater part of the 

 world, except the Central Paciiic. South Africa, however, is not 

 well off for Gulls, possessing representatives of only three species. 



Key of the Species. 



A. Largest, wiiig about 17 ; back slaty-black, 



head white L. dominicaims, p. 423. 



B. Intermediate, wing about 13 ; back lavender- 

 grey ; a lavender-grey hood in the breeding 



dress L. cirrhocephalus,pA27. 



C. Smaller, wing about 11 ; back lavender-grey ; 



head always white L. hartlaubi,^. 425. 



754. Larus dominicanus. Southern Black-backed Gull. 



Larus dominicanus, Licht., Verz. Doubl. p. 82 (1823) ; Layard, B. S. 

 Afr. p. 367 (1867) ; Bullei; B. New Zeal. p. 270, pi. 28, fig. 1 (1873) ; 

 Sharpe, eel. Layard's B. S. Afr. p. 607 (1884); Swinburne P. B. 

 Phys. 8oc. Eddn. ix, p. 200 (1886); FlecTc; Journ. Ornith. 1894, p. 

 379; Smmders, Cat. B. M. xxv, p. 245 (1896); Shelley, B. Afr. i. 



