4608 PIPING PLOVER. 
does not undergo extreme changes, and merely from darker 
to lighter. Several species breed in our climates, and their 
flesh is hardly esculeut. Although not marked by any strik- 
ing physical character, we regard the extensive group Avgialitis 
as a very natural one: it has numerous species in every part 
of our globe. The three European are modelled precisely 
after the same type as the present species, while the three 
other North American have each a strong distinctive character 
peculiar to itself; in the semipalmated it is the webbed toes, 
in the Wilson’s the powerful and acute bill, and in the kildeer 
its large stature and oddly coloured wedge-shaped tail. 
In all our plovers the bill is shorter than the head, rather 
slender, straight, cylindrical, depressed at base, obtuse and 
somewhat turgid at tip: the upper mandible is longitudinally 
furrowed two-thirds of its length, the lower is shorter: a 
remarkable character consists in the small opening of the 
bill, which is hardly cleft beyond the origin of the feathers. 
This peculiarity affords an excellent means of distinguishing 
them from the Gdicnemz, in which the gape extends to 
beneath the eye. The nostrils are basal, lateral, placed in the 
furrow, and covered by a membrane, leaving only a narrow 
longitudinal opening: the tongue is entire, obtusely lanceolate, 
channelled somewhat above, convex beneath. ‘The head is 
large in proportion to the body, and the eyes large even for 
the head; the forehead is prominent, and the face wholly 
feathered. The feet are either three or four toed, with the 
hind toe exceedingly small and raised from the ground: the 
naked part of the tibia is moderate ; the tarsi are longer than 
the middle toe, and reticulated ; the toes scutellate, margined 
by a narrow squamulosé membrane ; the middle toe is longest, 
and connected to the outer, at least to the first joint, by a 
membrane: even in the species that have the inner toe cleft 
there are traces of the membrane, which is so much developed 
in the semipalmated ring-plover: the nails are compressed, 
curved, and acute. ‘The wings are elongated, acute, and 
tuberculate : the first primary is longest, and after the second 
