BIRDS OF NORTH AND MIDDLE AMERICA. 147 
dd. Exposed culmen less than one-third as long as wing. 
e. A web between inner and middle (as well as between outer and middle) toes. 
J. Tarsus more than one-third as long as wing.....-. Micropalama (p. 204). 
J. Tarsus not more than one-fourth as long as wing..... Ereunetes (p. 209) 
ee. No web between inner and middle toes .....-.-------- Machetes (p. 218). 
cc. Anterior toes cleft to the base (no webs). 
d. Hallux present. 
e. Bill not distinctly if at all expanded terminally. 
f. Feathering on lores extending to nostrils, that on malar region extending 
nearly as far forward as anterior end of nostrils; inner webs of remiges 
marbled or freckled........-.-.---------------20- Tryngites (p. 225). 
ff. Feathering on lores not extending to nostrils, that on malar region not 
extending beyond posterior end of nostrils; inner webs of remiges not 
marbled or freckled. (roliz.) 
g. Middle pair of rectrices not longer than the rest; tail less than two- 
fifths as long as Wing .....-..-.------------0---- Canutus (p. 230). 
gg. Middle pair of rectrices distinctly longer than the rest; tail at least 
two-fifths as long as wing. 
h. Exposed culmen longer than tarsus. 
i. Bill stouter; tarsus less than one-fifth as long as wing, shorter than 
middle toe and claw.........---------+-- Arquatella (p. 238.) 
ii. Bill more slender; tarsus more than one-fifth as long as wing, 
longer than middle toe and claw. 
j. Bill distinctly decurved distally; middle toe, with claw, less 
than three-fourths as long as tarsus..-....-.-. Erolia (p: 249). 
4j. Bill not distinctly decurved distally; middle toe, with claw, 
four-fifths as long as tarsus.....--...-..-.- Pelidna (p. 256). 
hh. Exposed culmen shorter than tarsus........-.---. Pisobia (p. 266). 
ee. Bill conspicuously expanded (paddle-shaped) terminally. 
Eurynorhynchus (p. 302). 
dd. Hallux absent ............2002 2000022 eeeee eee ceeeeeee eee Calidris (p. 307). 
bb. Nasal fossze relatively narrow posteriorly, continued anteriorly as a broad 
groove for not more than two-thirds the length of the maxilla, or else (Actitis) 
inner web of remiges crossed by a broad band of white spots. (Tringinz.2) 
c. Bill not at all decurved distally. 
d. Tail shorter than tarsus (much less than half as long as wing), not graduated; 
exposed culmen much more than six-tenths as long as tarsus. 
e. Nasal groove extending for much less than two-thirds the length of maxilla; 
inner webs of remiges not crossed by a white band. 
@ According to Lowe (Ibis., 1915, 612) the Tringinz are easily distinguished from 
the Eroliine by the following osteological characters: Distal end of premaxilla more 
elongated and pointed, less elastic, and with slit-like depressions instead of pits; 
pterygoid processes long, ribbon-shaped, more parallel toward pterygoid articulation; 
maxillo-palatine process extending backward on either side of vomer, as a very 
attenuated pyriform or sac-like process, free for greater part of its course; inwardly 
projecting plate of maxillary not distinctly if at all fenestrated; line of culmen gradu- 
ally ascending to nasal region, where abruptly inclined upward; zygomatic arch or 
quadrato-jugal rod not making a distinct angle with maxillary process of premaxillary; 
supraorbital grooves conspicuous; postarticular process of mandible not hook-shaped; 
supra-occipital portion of skull (viewed from above) conical. 
The genera Bartramia, Numenius, Pheopus, and Mesoscolopax were not examin- 
ed. by Mr. Lowe, and may not belong to this group, in which I place them tenta- 
tively; Tryngites and Limosa, for the same reason, being provisionally referred to the 
Eroliine. 
