CEYLON RAILS, WADERS, GULLS, AND TERNS. 241 
which other aberrant Plovers, such as the Pratincoles and 
Crab Plovers, show considerable affinity, all being specialized 
offshoots from the same main stem.* In details of anatomy 
the two orders display marked resemblance, the Gaviz, 
however, being modified in outward form to fit them for their 
sea-faring life. Their wings are long and pointed, giving 
their flight speed and endurance ; their legs are short ; the 
front toes are webbed, while the hind toe is small and set on 
the foot at a higher level than the others ; the bill varies in 
the families and sub-families of the order. 
In their nidification also these birds resemble the Waders ; 
their eggs are of much the same character, being marked by 
spots of two different hues, and laid on the ground with little 
or no nest. The young are hatched covered with down, and 
are able to run about at once, though for a few days they are 
fed by their parents. 
The classification of the order varies considerably among 
different authors. By Dr. Blanford the Indian members are 
divided as follows :—The Skuas are placed by themselves in 
one family Stercorarivide ; the Gulls Larine, the Terns 
Sternine, together with the Skimmers Rhynchopine, of which 
no species occurs in Ceylon, form three sub-families of a 
second family Laride. 
The two families are outwardly distinguished thus :— 
1. Inthe Laride the bill has no cere, 7.e., membrane of skin 
covering the base of the bill from the forehead to the nostrils, 
while the claws are only moderately curved and not sharp. 
2. In the Stercorariide the bill is furnished with a cere, 
and the claws are powerful, boldly curved, and sharp. 
Family Laripa. 
As stated above, the Ceylon Laride fall into two sub- 
families, which may be distinguished by the shape of the bill :— 
A.—Larine.—The Gulls have the upper mandible longer 
than the lower and curved at the tip. 
B.—Sternine.—The Terns have both mandibles of equal 
length. 

* Mr. R. P, Lowe ** On the Crab Plove” Ibis, April, 1916, p. 337. 
