XXXV1 INTRODUCTION. 
naked ; toes four in number, the third and fourth connected at their base by 
a membrane ; the hind toe touching the ground at the tip (p. 621). 
Limosa, Srisson.—Bill very long, rather thick at the base, compressed, slightly 
curved upwards ; both mandibles grooved laterally to within a short distance 
of the point, which is somewhat dilated and blunt; tip of the upper 
mandible projecting beyond the lower one. Nostrils basal, placed in the 
lateral groove, narrow and longitudinal. Wings pointed, of moderate length, 
the first quill the longest. Tail short and even. Legs long and slender, a 
great part of the tibia naked. Three toes in front, one behind; outer 
and middle toes united at the base by a membrane, the inner toe nearly 
free ; middle claw dilated, recurved, and pectinated ; hind toe short, and 
articulated fairly high upon the tarsus (p. 623). 
NuMENIvs, Srzsson.—Bill long, slender, and decurved to the point, which is 
hard ; upper mandible rather longer than the lower, rounded near the end 
and grooved along three-fourths of its whole length. Nostrils lateral, linear, 
pierced in the groove. Wings moderate, the first quill the longest. Legs 
rather long, slender; tibia partly naked; three toes in front, united by a 
membrane as far as the first joint ; one toe behind, articulated low upon the 
tarsus and touching the ground (p. 627). 
Order GAVIA. 
Family LARID&. 
Bill without a cere ; sternum with two notches on each side of the posterior 
margin ; toes partially or fully webbed ; claws feeble or moderate. 
Subfamily STERNINA. 
HYDROCHELIDON, Boze.—Bill about as long as the head, nearly straight, tapering. 
Wings long and pointed, the first quill the longest. Tail short, very slightly 
forked. Legs short ; the tibia bare for some distance ; the tarsus compressed, 
anteriorly scutellated ; three toes in front connected by deeply scalloped webs ; 
hind toe small and elevated ; claws long, slender, curved (p. 633). 
STERNA, Srésson.—Bill longer than the head, nearly straight, compressed. 
Wings long, pointed, the first quill-feather the longest. Tail distinctly forked 
in varying degrees. Legs slender, naked for a short space above the tarsal 
joint ; the three toes in front united by membranes which are concave in 
front or semi-palmated ; hind toe free ; claws curved (p. 639). 
Anous, Stephens.—Tail moderately long, rounded, slightly emarginated. Three 
anterior toes united by 2 very full web, hind toe small ; claws strong and 
curved. Otherwise much as in Sterna (p. 655). 
Subfamily Larina, 
XeEmA, Leach.—Bill rather shorter than the head, moderately stout ; the upper 
mandible decurved from beyond the nostrils to the tip, the gonys angular 
and advancing upwards. Nostrils basal, lateral, linear. Wings long, the 
first quill the longest. Tail distinctly forked. Legs moderately long ; the 
