OKTHOPTERA FORFICULARI.E. 209 



with very bluntly rounded apex. Forceps of male broken in the only speci- 

 men seen, but evidently pretty long and moderately stout, the portion (half?) 

 remaining being as long as the last two segments of the abdomen, straight, 

 equal, separated at base by the pygidium, with a very stout, sharp, triangu- 

 lar, interior tooth embracing the pygidium, and with two minute distant 

 teeth or tubercles beyond ; in the female distant at base, straight, flattened, ' 

 simple, unarmed, tapering regularly, with not the slightest inward curve, 

 to a bluntly rounded tip, one-third the width of the base. This peculiarity 

 reminds me of a specimen of Labidura riparia I have seen with perfectly 

 straight and laminate forceps 1 . 



Length of body, excludingforc.eps, j 17.5 mm , $ 17.5 mm ; breadth of head, 

 $ 2.25"""; of pronotum, f, 1.75"""; of closed tegmina, / '3 mm ; of abdomen <? 

 3.5 mm ; length of forceps, <? (broken) 4 nim , ? 3-3.5"" ; breadth at extreme 

 base, t 0.8 nini , ? 0.75 mm ; at tip, ? 0.25 mm . 



This is the only one of our American fossil species with toothed forceps. 



Florissant. Three specimens, Nos. 2877 (<?), 1832, 11208 (?). 



5. LABIDUROMMA TERTIARIUM. 



PI. 16, Figs. 18, 21 ( 3 ), 15 ( 9 ). 



Labidura tertiaria Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., II, 447-449; III, 259; IV, 519. 



A single male specimen (Fig. 18), found by Mr. Jesse Randall, and brought 

 home bv the Survey under Dr. Hayden, formed the basis of the following de- 

 scription : The head, which is badly preserved, is of about equal length and 

 breadth behind the labrum, so that as a whole it is longer than broad, but 

 it is slightly narrower than the pronotum, and has large eyes, reaching bad: 

 nearly to the hind border characters which are scarcely in keeping with 

 the reference of the insect to Labidura ; with no other genus, however, does 

 it accord so well. The antenna? are too fragmentary to furnish us any clew 

 tn their structure, and of the mouth parts nothing can be determined. The 

 proiiotimi is of about equal length and breadth, quadrate, the anterior angles 

 bluntly rounded, the posterior border very broadly convex, the margin no- 

 where rlevnied ; there is a slight but distinct median sulcation, fading pos- 

 teriorly. The iv-r of the thorax is of the same width as the pronotum: the 

 ti-Miniiia an- twice as long as the pronotum, squarely docked at the tip; the 

 folded wings i' :icli more than half as far again beyond the tip ot the teg- 



I'rnr. lln-t. >or. N.ll. lll--t., Mil. 1-, ].,'. ..'.'l-;li".. 



\nl. Mil 14 



