66 



COOK 



Color walnut to mars brown and seal brown ; posterior margins of 

 segments in some specimens darker and in others lighter ; legs some- 

 what paler than body, but of the same color. Young specimens with 

 a slight reddish or pinkish tinge. 



Clypeus usually with four setiferous punctations on each side ; often 

 with five, rarely with three, and in such instances the numbers of the 

 two sides generally unequal. 



First segment with lateral corners sharper and more produced than 

 in T. hebes, so that the processes of the second segment appear some- 

 what shorter than in that species. 



Segments with transverse and other sutures less distinct than in 

 T. hebes, but the surface somewhat more distinctly punctate and with 

 very minute and irregular furrows and striae. The coarser longitudinal 

 or oblique striations of the ventral surface of the segments cease well 

 below the pores, especially caudad. The posterior transverse suture 

 curves backward to pass around the pore. 



The posterior part of the body tapers more than in T. hebes, though 

 less in some individuals than in others, since two or three of the rear 

 segments are sometimes much shortened or compacted together. 



Anal valves rather more prominent, thick, and swollen than in T. 

 hebes. 



Gonapods differing from those of T. hebes, as described by Boll- 

 man, in having the mesial part of the anterior lobe shorter than the 

 ventral plate, and the apex of the posterior lobe turned outward. The 

 posterior gonapod differs also in that the apex is long, subcylindric, 

 and pilose, instead of "small, thick, and rounded, beneath produced 

 into two serrated plates." 



Fifteen specimens were examined, nine of which are mature males. 

 They were probably collected in the vicinity of Palo Alto, though the 

 vials contain no indications of locality, other than ' California.' A 

 single female nearly 70 mm. long and 8 mm. wide may represent a 

 distinct species, though closely resembling the others, except in the 

 much greater size. 



TYLOBOLUS HEBES Bollman. 



Spirobolus hebes BOLLMAN, Entomologica Americana, n, p. 228, 1887; Ann. 

 N. Y. Acad. Sci., iv, p. 31, 1887; Bull. 46, U. S. Nat. Mus., pp. 50, 65, 

 1893. 



This species belongs undoubtedly to the present genus, and seems 

 to be very closely allied to the preceding. The National Museum 

 seems to possess only the female of the original pair described by 



