Birds of Celebes; Laridae. 
893 
ORDER LARI. 
The systematic position of the Gulls — whether they should be placed 
neai-er to the Plovers or to the Petrels — is not yet decided; perhaps an inter- 
mediate position would he most correct. They have the following characters 
whereby they may be distinguished as an order. They are of more or less ex- 
clusively natatorial habits, feeding chiefly upon flsh, and furnished with webbed 
feet (in some genera the webs much indented) , differing, especially by the former 
point, from the Chamdriidae ; the young are covered with down and spotted, and 
are able to leave the nest at an early age; the eggs are richly spotted, and do 
not apparently exceed 3 in number; the nostrils are schizorhine — wherein 
they differ from the Tuhinares and Steganopodes; further from the former by the 
shape of the tongue, coracoid, furcula and hypotarsus, etc. (Gadow), from the 
latter by the hind toe, when present, not being webbed and joined on to 
the other toes; the bill is simple, not furnished with a nail at the tip or ser- 
rations or lamellae at the edges; the wing is long, the ulna exceeding the 
humerus — whereby they differ from the Ducks, as well as by their eggs, young, 
and various osteological characters. 
FAMILY LARIDAE. 
Mr. Howard Saunders divides the Lari or Gaviae into two families, 
Laridae and Stercorariidae , the foTiner being distinguishable by their “bill with- 
out a cere ; sternum with two notches on each side of the posterior margin ; 
toes partially or fully webbed; claws feeble or moderate”. He subdivides the 
Laridae into Sterninae, Rhgnchopinae and Larinae; the Sterninae have a straight, 
tapering bill with both mandibles of about equal length, whereas in the Larinae 
the tip of the maxilla turns down over the mandible, while the bill of Rhgncliops 
is of abnormal appearance, the lower mandible projecting considerably beyond 
the upper one. 
GENUS HYDROCHELIDON Boie. 
These small. Marsh Terns are distinguishable from the other Terns by 
their having the feet webbed only about as far as the first joint of the middle 
toe, and the feet do not appear to be used for swimming. There are four 
species, generally of dusky plumage. 
380. HYDROCHELIDON LEUCOPTERA (Meisii. Sch.). 
M^hite-winged Black Tern. 
a. Sterna leucoptera (I). Meisner & Scliinz, Vog. Schweiz 1815, 264, (II) ^'launi,., Vog. 
Deutschl. X, 214, t. 257 (1840); ( 3 ) Stejii., Bull. U. S. Nat. Mus. 1885, Nr. 29, 
316; ( 4 ) Bns. & Worces., B. Menage Exped. 1894, 31. 
