ATOPETHOLID MILLIPEDS — HOFFMAN AND ORCUTT 159 



exceeding the tip of the laminate tibiotarsus; by the elongated coxal 

 lobes of the third legs of males; and by the coxal apices of the anterior 

 gonopods, which are not produced distad nearly to the extent seen in 

 Arinolus. In other characters the two genera appear to be very 

 similar, although we have not been able to study material of Piedolus. 



Discussion: Subsequent to its original description, Piedolus fell 

 into complete obscurity to the extent that even its author failed to 

 notice the name when subsequently erecting the closely related genus 

 Arinolus in 1940 and when listing the known atopetholid genera in 

 1949. The original generic diagnosis compared the genus only with 

 Atopetholus; aside from the differences noted, most of what is said 

 applies to all atopetholids, and the most useful generic characters are 

 to be found in the illustrations of the gonopods. 



Piedolus utus Chamberlin 



Piedolus utus Chamberlin, 1930, p. 118, 2 figs. 



Holotype: Male, collection of R. V. Chamberlin, from St. George, 

 Washington County, Utah, collected on April 3, 1929, by Lowell 

 Woodbury. 



Diagnosis: With the characters of the genus. 



Description (data taken from the original description): 

 Male 30 mm. long and 3.0 mm. in diameter, with 44 segments. 



Color in general deep brown or almost black, the segments lighter 

 beneath; head and anal segment uniform in color except a median 

 pale line above clypeal incision; legs and antennae concolorous with 

 body. 



Clypeal foveolae 5-5. 



Lateral ends of collum acute, anterior lateral edge concave adjacent 

 to level of eye. 



Sternite of anterior gonopod broad and slightly arched mesially, an 

 accessory sclerite present at base of coxite on each side as in most 

 forms of Arinolus, the coxites narrowing mesiad, and separated by 

 what appears to be a vinculum formed from sclerotized membrane 

 from the sternite. Details of the basal structure of both gonopods 

 not shown but presumably as in Arinolus. Telopodite of posterior 

 gonopod with the distal half set off by a constriction, becoming very 

 broad, laminate, and subovoid in shape. Proximad of the constric- 

 tion, on the caudal side, originates the long, slender, slightly sinuous 

 solenomerite, which carries a visible groove. 



Genus Tarascolus Chamberlin 



Tarascolus ChamberliD, 1943a, p. 25. 



Type species: Tarascolus bolivari Chamberlin, by original designa- 

 tion. 



