74 TERTIARY INSECTS OP NORTH AMERICA. 



Length of body, ll ram ; of cephalothorax, ;Y nn ' ; breadth of same, 2.2 mlu ; 

 of abdomen, 6.4 mm ; length of first pair of femora, 6 ram ; second pair, f) mm ; 

 second tibiae, 4 mm ; third femora, 2 mm ; third tibue, 2.4 mm ; fourth femora, 

 3.25 mm . 



Besides its very much greater size, this species differs greatly from the 

 other in the form of the cephalothorax. 



Florissant. One 9, No. 13521, preserved on a dorsal view. 



2. THERIDIUM SECLUSUM. 

 PI. 11, Fig. 20 ( $ ). 



Male. Cephalothorax stout, square oval, a little longer only than 

 broad, the front broadly and regularly rounded. Cheliceres rather stout, as 

 long as half the width of the corselet, tapering a little, rounded at the apex, 

 the outer edge straight, the inner rounded. Last joint of palpi nearly as 

 large as the cheliceres, oval, on a stalk as long as the cephalothorax. These 

 tun parts are incorrectly represented on the plate, where the palpi and cheli- 

 ceres appear as one great piece. Abdomen rather small, oval, narrower 

 than the cephalothorax, but of about the same length. Legs long and 

 slender, the first pair particularly long, and the second pair considerably 

 longer than the fourth, which is unusually slender ; all the legs are furnish, d 

 with numerous spines, apparently arranged in three rows and clustered much 

 more numerously at the distal end of the femora and tibia; than elsewhere ; 

 tlir spines are moderately slender and about as long as the width of the 

 joints, separated from one another by about their own length, sometimes a 

 little less. 



Length of body, 4.5 min ; of abdomen, 2.25 mm ; width of cephalothorax, 

 1.65 mm ; of abdomen, 1.2 mra ; length of cheliceres, 0.75 nim ; of first pair of 

 legs, 15 mm ; its femora, 4.5 mm ; tibia?, 4.5 mm ; tarsi, 6 mm ; second pair of legs, 

 12 mm ; femora, 3.75 lum ; tibiae, 3.75 mm ; tarsi, 4.5 mm ; third pair of legs, 5.25 mm ; 

 femora, 1.4 mm ; tibiae, LI"; tarsi, 2.7 o mm ; fourth pair of legs, 9 mm ; femora, 

 3.5 mm (!) ; tibise, 1.5 (?) ; tarsi, 4 mm . 



The species is very much smaller than T. opertaneum, besides having 

 a very different corselet, 



Florissant. Nos. 2286, 7816, 9026. All the specimens appear to be 

 males. 



