No. 1810. DESCRIPTIONS OF NEW MILLIPEDS— COOK. 153 



Coalesced pleura? of seventh segment of male crossed by a relatively 

 slight, straight ridge, not carried up into a fold-like, arcuate crest, as 

 in Onychelus. 



The narrowing of the first segment at the sides in Eurelus and 

 Onychelus does not result from a change in the anterior margin, which 

 is much the same as in Arctobolus. The principal difference lies in the 

 much straighter posterior margin of Eurelus which does not curve 

 back from the lateral angle of the segment, as in Arctobolus, but passes 

 directly upward. 



EURELUS SOLEATUS, new species. 



Type.— Cat. No. 801, U. S. National Museum. Collected at Fal- 

 furrias, Starr Count}^, Texas, August, 1906, by O. F. Cook. 



Length of male about 65 mm., width nearly 8 mm. Number of 

 segments 48. 



Color in life, dull olive brown with somewhat grayish posterior 

 margins, not at all reddish or yellowish, as in Arctobolus. On being 

 placed in alcohol the dark bands appear darker and the light bands 

 lighter, and the contrast accordingly much greater, as though black 

 and pale yellow. 



With age the alcoholic specimens become very dark, blackish-green, 

 with the margins of the segments paler, and appearing yellowish or 

 brownish if the specimens begin to dry out. The first segment and 

 the dorsal part of the last segment appear distinctly paler than the 

 others, both in the fluid and out. 



Clypeal foveolre five on each side, sometimes only four; surface of 

 clypeus and vertex with rather remote, irregularly scattered wrinkles, 

 otherwise smooth and shining. 



Eyes rounded-polygonal, 43 or 44 ocelli, arranged in nearly vertical, 

 somewhat curved rows, counted as follows, beginning at the back: 

 6, 7, 8, 7, 6, 6, 4. In the other eye of the same specimen the arrange- 

 ment of the ocelli seemed to be 5, 6, 7, 7, 7, 6, 4, 1. In an eye of 

 Onychelus obustus the ocelli were counted in rows of 5, 5, 6, 6, 5, 3. 



First segment with three or four short irregular striations above the 

 lateral angle, not present in Onychelus obustus. The angle is more 

 pointed than in Onychelus, and the anterior thickened margin is 

 broader and more prominent and also more distinctly sinuate because 

 of the deeper emargination. 



Second segment with a distinct raised flange along the anterior 

 ventral margin, but not nearly so prominent as in Onychelus. 



Surface of segments with a rather dull luster, minutely punctate 

 over all the exposed surface, but somewhat more on the midbelt than 

 on the hindbelt, which becomes slightly more prominent on the sides 

 and below, and may then have the surface roughened by indistinct 

 granules or by irregular shallow, seal-like depressions, above the 

 regular ventral striations. 



