BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



States, tlie collection contains a full-grown c? and a young 9 of the prin- 

 cipal form from Boulder, Colo,, captured June 29; a full-grown <? and 

 a young 5 of the var. jS, iindulata, the $ from Idaho (captured July 6), 

 the ? from Manitou, Colo. (July 12), as also several examples of the 

 var. y, dehilis, collected at Boulder, Colo, (among them one ^ ad.) (June , 

 24), Golden, Colo. (July 3), and the Great Salt Lake, Utah (July 23). In 

 the adult male, both of var. iS and var. y, the abdomen is wanting. I 

 have also examined many specimens of the principal form and of var. 

 y from Wisconsin. The measures above given of these two varieties are 

 taken from examples from that State. 



I must confess that I am not at all certain that T. elongata is specifi- 

 cally different from the true T. extensa (Linn.) or T. norimcki L. Koch. 

 The number of the teeth of the claw-furrow and the arrangement of 

 these teeth appear to be slightly different in these two forms, but these 

 characteristics are somewhat variable in both of them. The European 

 T. extensa has the sternum black, with a triangular yellow spot or line 

 in the middle; but this is also the case in the variety undulata of the 

 American species; also in T. extensa $ the apophysis of the tibial joint 

 of the palpus is furnished with a short blunt process toward the middle 

 of the inner side. At all events, T. elongata differs less from T. extensa 

 than do for instance T. islandri (Scop.) Thor. and T. obtusa C. L. Koch. 



Section RETITELAEI^E. 



Fam. THERIDIOID.^. 



Gen. LiNYPHiA Latr,, ISOi. 

 3. L. oroiyhila n. 



Cephalothorax, mandibles, maxillte, palpi, and legs pale testaceous; 

 cephalothorax with black margins; eyes black, large, close together, 

 and prominent, the four central ones forming a trapezium broader 

 behind than in front and as long as broad behind, little shorter than 

 the height of the clypeus; first pair of legs the longest; thighs and 

 tibi[B with traces of black rings; abdomen olive-colored, with sinuated 

 oblique bands or lines on each side above, followed on the back by a 

 short row of transverse angular lines, sides also with a row of spots 

 below, these markings being all of a pale yellowish hue, as is also at 

 least the posterior part of the belly and the region around the mamilloe; 

 vulva pale reddish-brown, with a longitudiual narrow middle ridge 

 below, and forming, seen from the side, an oblong protuberance slightly 

 two-toothed at the extreme apex. — 9 ad. Length about 2| millim. 



Female. — Cephalothorax shorter than patella and tibia of the fourth 

 pair together, oblong, rounded in the sides, with the pars cephalica 

 rather large and high ; the breadth of the clypeus is a little greater than 

 half the breadth of the pars thoracica, the height of the clypeus is but 

 little greater than the length of the area of the central eyes. Eyes 

 large, prominent, and close together, not much differing in size; the 



