216 



THE MYKIAPODA OF NORTH AMERICA. 



" Stenmia Mmida. Body composed of seventeen double segments, distinctly divided on 

 the dorsal mesial line. Body depressed, margins of segments quite prominent and curved 

 forwards near the head, in the middle and posteriorly transverse or curved slightly back- 

 wards. Surface of each segment covered with five rows of distinct tubercles, arranged 

 somewhat in quiucuncial order. From the direction of the tubercles the lateral and 

 posterior margins of each segment appear serrated. First cervical segment smaller than 

 the next, rounded anteriorly, straight and narrower behind, and obliquely truncated on the 

 sides. The posterior segment about equal to the next in length, is triangular, the apex 

 armed with a stiff hair. Color pale red above, feet and ventral surface flesh colored. 



Length 6". Under decayed logs." 



Sager, Proc. Acad. Nat. Sci., 1856, vol. viii, p. 109. 



I have never seen a specimen corresponding entirely with this description. Is it possi- 

 ble that Mr. Sager's species is either P. serratus, Say, or P. setiger, Wood I 



P. Canadensis. 



1'. saturate brunneus; antennis pubesccntibus, vix clavatis; scutis, singula- squaniis 8 in seric duplici dis- 

 posilis ornato, ruarginibus lateralibus obsolete serratis ; appendiuibus masculis (Fig. 43) pilosis, spina terminalc 

 modica, curvata. 



Deep brown; antennae pubescent, scarcely clavate; scuta eacb ornamented with 8 squama, arranged in a 

 twofold series; lateral margins obsoletely serrate; male appendages hairy, their terminal spine moderate, curved. 



1'. Canadensis, Newport, Ann. and Mag. Nat. Hist., vol. xiii, p. 265; Catal. Brit. Mus., Myriap. 



" Gervais, Suit, a Buffon, Apteres, vol. iv, p. 106; Exp. L'Amer. du Sud (Castelneau), Myriap., 



p. 6. 

 " P. serratus, Soy," II. De Suvssure, Mem. Soc. Nat. Hist. Geneva, vol. xv, p. 325. 



The color of this species is a dark brown, verging somewhat towards a chestnut, with, 



in some individuals, still more of the red. The median fur- 

 row of the 1 vertex is strongly pronounced. In other respects 

 the head agrees with that of P. cerasinus. The antenna' are 

 rather more pubescent than in that species. The scuta are 

 ornamented with a double row of scales on their posterior sur- 

 face. These rows are composed each of four broad rectangular 

 scales. There is frequently on each side 1 a raised convexity or 

 umbo Lying outside of these. The serratures in the lateral 

 margins of the side plates are very minute and frequently en- 

 tirelj obsolete. The last scutum is triangular, with its obtuse apex decimate. The male 



Fig. 43. 



Fig. II 



