366 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



Eeteractitis (^ Stejneger, Auk, i, July, 1884, 236. (New name to replare 

 Heteroscelus Baird, thought to be preoccupied.) 



Medium-sized Tringinae (wing 160-180 mm.) with stout bill, tarsus 

 shorter than exposed culmen (though longer than middle toe with 

 claw), planta tarsi with scutella small (sometimes broken or irregular), 

 and color of upper parts wholly plain brownish gray. 



Bill straight and rather stout, its depth at base equal to nearly 

 one-sixth the length of exposed culmen, the latter longer than tarsus; 

 nasal groove broad, extending half way to tip of maxilla (in H. 

 hrevipes) or two-thirds the distance (in H. incanvs); gonys about as 

 long as mandibular rami (//. hreviyes) or decidedly shorter {H. 

 incanus), faintly convex; culmen slightly but decidedly decurved 

 terminally. Wing long and pointed, the longest primary (outermost) 

 exceeding distal secondaries by about one-half the length of wing. 

 Tail nearly half as long as wing (somewhat shorter in H. hrevipes), 

 very slightly rounded. Tarsus slightly shorter than exposed culmen 

 but longer than middle toe with claw, the acrotarsium with trans- 

 verse, slightly obli(|ue, scutella, these becoming smaller and finally 

 broken into small scales on upper portion; planta tarsi with the 

 scutella much smaller, sometimes broken up into sm.all scales; bare 

 portion of tibia short (much less than half as long as middle toe), 

 covered with sm.all scales, those on posterior side sometimes in form 

 of small transverse scutella; lateral toes decidedly shorter than 

 middle toe, the outer toe slightly longer than the inner one; basal 

 phalanges of outer and middle toes connected by a deeply incised 

 web, but web between inner and middle toes much smaller, practically 

 absent. 



Coloration. — Above plain brownish gray, the remiges, primary 

 coverts, etc., darker; beneath white, more or less barred with brown- 

 ish gray or dusky in summer, clouded or suffused with grayish ante- 

 riorly and laterally in winter. 



Range. — Coasts and islands of Pacific Ocean. (Two species). 



KEY TO THE SPECIES OP HETEROSCELUS. 



a. Nasal groove (measured from latero-f rental antia) much more than half (about 

 two-thirds) as long as exposed culmen; upper tail-coverts uniform gray, or 

 merely edged (narrowly) with white; summer adults with abdomen and under 

 tail-coverts barred with dusky. (Alaska and Yukon Territory to northeastern 

 Siberia, migrating to Lower California, Galapagos Islands, Hawaiian Islands; 



etc.) Heteroscelus incanus (p. 3G7) 



aa. Nasal groove (measured from latero-frontal antia) only about half as long as ex- 

 posed culmen; upper tail-coverts distinctly barred with white; summer adults 

 with abdomen and under-tail coverts immaculate white. (Shores and islands of 



a From e7epos=different and 6 dK-TiTr7s=an inhabitant of the shore. (Stejneger.) 



