NO. 1847. THE LADDER-BACKED WOODPECKERS— OBERHOLSER. 141 



(/. Smaller (wing less than 90 mm.); sides of breast spotted with black; primary- 

 coverts with less white Dryobates scalaris leucoptihirus. 



y. Lower surface much lighter. 



c. Smaller (wing less than 100 mm.); outer webs of primary coverts with very little 



or no white; postocular stripe rather broader; malar stripe obsolete at base 



of bill. 



d. Under parts lighter; size decidedly larger (wing not less than 95 mm.); lower 



surface less heavily spotted with black; black bars on back and tail 



broader Dryobates scalaris graysoni. 



d' . Under parts darker; size decidedly smaller (wing less than 95 mm.); lower 

 surface more heavily spotted with black; black bars on back and tail 



narrower Dryobates scalaris azelus. 



cf . Larger (wing not less than 100 mm.); outer webs of primary coverts conspicu- 

 ously spotted with white; postocular stripe not so broad; malar stripe not 

 obsolete at base of bill. 

 d. Decidedly smaller (wing averaging less than 104 mm.); ventral surface 

 lighter; lighter above (the white bars on back averaging wider and more 

 regular, the black bars narrower); black bars on posterior lower parts 



averaging less heavy Dryobates scalaris lucasanus. 



d' . Decidedly larger (wing averaging more than 104 mm.); ventral siu-face 

 darker; darker above (the white bars on back averaging narrower and 

 less regular, the black bars wider); black bars on posterior lower parts 

 averaging somewhat heavier Dryobates scalaris eremicus. 



DRYOBATES SCALARIS SCALARIS (Wagler). 



Piciis scalaris Wagler, Isis, 1829, p. 511. 

 Picus gracilis Lesson, Rev. Zool., 1839, p. 41 (Mexico). 



Picus orizabae Cassin, Proc. Acad. Nat. Sci. Phila., 1863, p. 196 (Jalapa, Vera 

 Cruz, Mexico). 



Chars, suhsp. — Size medium (wing of male averaging about 96 

 mm.); white bars of back wider than the black interspaces; exterior 

 webs of three outer pairs of tail-feathers barred throughout with 

 black and wliite, although the black bars occasionally incomplete 

 basally; outer webs of primary coverts shghtly spotted with wliite; 

 malar stripe more or less obsolete at base of bill; lower surface 

 smoky browTiish; sides of breast and body hghtly spotted with black. 



Description. — Adult male, No. 37432, U.S.N.M.; Orizaba, Vera 

 Cruz, Mexico, January 15, 1864; F. Sumichrast. Crown and nape 

 black, the feathers of the former subterminally dull wliite, terminally 

 scarlet vermihon, this producing a mottled effect on the top 

 of the head, but merging into a solid band of red on the occiput 

 and anterior hind neck; remaining upper parts black, all, excepting 

 the superior tail-coverts, barred with white — these white bars nearly 

 all \\dder than the black interspaces; tail black, the three external 

 pairs of rectrices, including the dwarfed outermost one, much barred 

 with dull white, except on basal portion of inner webs of the second 

 and third; the fourth pair spotted wdth white on margin of outer 

 vane; wdngs black, the remiges spotted conspicuously on both webs 

 with white, these spots forming, on tertials fairly well-defined bars, the 



