THE MTRIAPODA OF NORTH AMERICA. 203 



This species differs from 1. canaliculatus in it's smaller size, the absence of hairs on the 

 anterior, and their paucity on the posterior portion of the body, and in the mucro being 

 larger in proportion to the rest of the animal. 



Hub. Chester County, Pennsylvania. — Dr. H. C. Wood, Jr. 



I. CINEREERONS. 



I. brunneus, cinereo annulatus; capitis superfieie antica cinerea; inucrone nullo; squama preanali triangula, 

 haud acuminata. 



Deep brown; antennae filiform, long, pilose, clavate; scuta below deeply and closely canaliculate, above some- 

 times obsoletely so; segments 33 ; mucro none. 



I. cinerefrons, Wood, Proc. Acad. Nat. Sci., 1864, p. 13. 



The color of this species is dark brown. The anterior surface of the head is an ob- 

 scure gray color, with a dark band. There is between the upper and anterior surface of 

 the head a well-marked angle, almost an elevated ridge. The lower margin is fringed 

 with a few hairs, and is emarginate and armed with a few denticules. The triangular 

 eyes are connected by a distinct, impressed line. On the upper portion of the anterior 

 surface of the head are two round, light dots, surrounded by a darker tint, The antenna? 

 are wanting in the only specimen, a female, that I have seen, Avhich is so mutilated that 

 1 cannot say certainly of how many segments it was composed ; the number, however, 

 was probably either thirty-four or forty-five. The first scutum has very small, lateral 

 processes. It is light brown, bordered with a dark band, edged with a grayish tint. The 

 anterior portion of the body is of a lighter shade than the posterior, and has the grayish 

 annuli more distinctly pronounced. The anal scutum is not mucronate. The anal scales 

 are not pilose. 



Hab. Oregon. — Smithsonian Institution. 



I. Milesii. 



I. saturate brunneus; antennis filiformibus, longis, pilosis, clavatis ; scutis infra arete et valde, supra iuterdum 

 obsolete, canaliculars ; segmentis 33 ; mucrone nullo. 



Brown, annulate with ash color; auterior surface of the head cinereous; uiucro absent; preanal scale triangu- 

 lar, not acuminate. 



I. MiLEsir, Wood, Proc. Acad. Nat. Sci., 1861, p. 13. 



