THE MYRIAPODA OF NORTH AMERICA. 179 



A careful examination of two specimens of sexspinosus from Cheha- 

 lis, W. T., proves, as Dr. Wood has previously shown, that the western 

 and eastern specimens should be separated. The main difference lies 

 in the hirsuteness of the first antenna I joints ; the differences mentioned 

 by Wood are hardly sufficiently distinct to separate the two forms. * 



15. Scolopocrytops nigridius. 



1887 — Scolopocryptops nigridius McNeill. Proc. U. S. Nat. Mus., 333 (Bloomington, hid.)', 

 Bollmau, Aim. N. Y. Acad. Nat. Sci., 107, 1888 (Knoxville, Tenn.); Bollman, 

 ibid., 110 (Beaver Cr., Term.): Bollman, ibid., 112 (Mossy Cr., Tenn.). 



Habitat. — Monougahela City, Pa.; Bloomington, Greencastle, Salem, 

 Indiana; Chapel Hill, N. C.; Beaver Greek, Mossy Creek, Knoxville, 

 Tenn. 



Etymology. — Latin, blackish. 



For the sake of completeness I give the following description of ni- 

 gridius. 



Head, antennae, first and last dorsal segments reddish brown; other 

 parts greenish brown ; legs paler, with the femoral and tibial joints of the 

 posterior pairs turquoise- green beneath. Moderately robust; sparsely 

 pilose; rather densely punctate, especially on head. Antenme rather 

 short, articles rather long, all except the first two densely hirsute. 

 Ooxaj of prehensorial legs strongly callous, sinuate; coxal tooth short 

 and blunt. Anal legs short, tarsi densely pilose as in gracilis ; infe- 

 rior spine large, interior small. Tarsi of anal and penultimate pairs of 

 legs unarmed, second tarsal joint, except that of the last four pairs of 

 legs, armed above. All the dorsal plates except the first three margi- 

 nate; two indistinct short sulci on the posterior part of the segment. 

 Anal pleurae scabrous, densely porous; spine large, robust. Anal 

 sterna wide, sides slightly rounded, posterior margin emarginate. 

 Length 25-40"""; length of anal legs 6-9""". 



This is the species mentioned by Cope (Proc. Amer. Phil. Soc., 179, 

 1869) as an undescribed Scolopocryptops with a " greenish body and a 

 reddish head? 



16. Scolopocryptops gracilis. 



1862. — Scolopocryptops gracilis Wood. Journ. Acad. Nat. Sci. Phila., 38 (Ft. Tcjon, 

 Col.); Wood, Trans. Amer. Phil. Soc, 173, 1865. 



1862. — Scolopocryptops lanatipes Wood. Journ. Acad. Nat. Sci. Phila., 39 (California); 

 Wood, Trans. Amer. Phil. Soc, 175, 1865; Kohlrausch, Archive Naturg., 

 56, 1881; Unde.rwood, Ent. Amer., 62, 1887. 



1870. — Scolopocryptops calif omica Humbert & Saussure. Rev. & Mag. Zool., 204 (Cal- 

 ifornia); Humb.& Sauss., Miss. Sci. Mex., 1872. 



Habitat. — Upper and Lower California. 



Etymology. — Latin, slender. 



Recent writers have used the name lanatipes for this species; but, as 

 gracilis preceded lanatipes iu Wood's monograph, it should be em- 

 ployed. 



