MYRIAPODA 57 



from the John Day Valley, Oregon, and are described as having the 

 carinae and last segment yellow. 



CHONAPHE ERUCA (Wood). 



Polydesmus eruca WOOD, Proc. Acad. Nat. Sci. Phila., p. 8, 1864; Trans. 



Am. Phil. Soc., xin, p. 227, 1865. 

 Strongylosoma eruca BOLLMAN, Bull. 46, U. S. Nat. Mus., p. 122, 1893. 



The generic position of this species can not be determined with con- 

 fidence, but there need be no doubt that it belongs with the present 

 series of American genera, rather than with the European genus 

 Strongylosoma Brandt. This disposes of a long-standing anomaly of 

 distribution, since no other species of Strongylosoma, nor anything 

 related to it, is known from North America. The present species is 

 assigned to the genus Chonaphe on the basis of three female specimens 

 collected by Prof. C. V. Piper at Pullman, Washington, which may 

 prove to be females of Chonaphe armata, though they are distinctly 

 more robust and convex, and with the carinae proportionally much 

 smaller than the females of other species of the related genera. They 

 agree fairly well with Wood's description, except in color, which is 

 very pale grayish, slightly tinged with brownish in one individual. 

 Wood's specimens were also all females, and as they, as well as the 

 type of Harger's species, were from Oregon, the presumption of spe- 

 cific identity is somewhat strengthened, though the degree of sexual 

 dimorphism which this would imply is rather unusual among the 

 Diplopoda. 



Isaphe gen. nov. 



Type. Isaphe convexa, from Idaho. 



Antenna? subfiliform ; joints 2 to 5 equal, joint 6 slightly longer and 

 thicker than the others ; olfactory cones 4. 



First segment semielliptic, nearly as broad as the second, about twice 

 as wide as long. 



Lateral carinse rather narrower than in related genera ; posterior 

 corner rounded, produced only on a few posterior segments. 



Repugnatorial pores sublateral, opening in small pits of the outer 

 slope of the strongly thickened margins of the carinoe ; pore formula 

 normal. 



Gonapods with basal joint moderately prominent ; second joint with 

 a somewhat bulbous base on which are inserted two long, slender, 

 tapering prongs nearly equal in length and size, and strongly connivent 

 at the apex. 



The dorsal convexity is notably greater than in other West Amen- 



