424 The Arachnida of Colorado. 



Comicularia communis Em. 



Fort Collins, sifting leaves, Februarj' (Baker). 



Tmeticus sp.? 



One female, West Cliff. 



Tmeticus flaveolus Bks. 



Fort Collins, one male, under stones, February (Baker). 



Erigone coloradensis Keys. 

 Described from the State. 



Erigone caciuninum Tlior. 



Gray's Peak, under stones, JUI3' (Thorell). 



Erigone strabo Thor. 



Arapahoe Pass, 11-12,000 feet, July (Thorell). This and the 

 preceding species do not belong to the genus as restricted ; thej 

 are unknown to me. 



Tiso spirotubus nov. sp. 



Leugth 1.4 mill. Cephalothorax and sternum yellow-brown, abdomen 

 black, with some small scattered white dots; legs and palpi pale yellowish. 

 Cephalothorax low, broad in front, head $ quite suddenly, but only slightly 

 elevated; tlie M. E. form a trapeze plainly longer tlian broad behind, the A. 

 M. E. smaller than other eyes and nearly touching; mandibles small, un- 

 armed; legs of moderate length, tarsi plainly shorter than the metatarsi, a 

 small spine behind on the under-side of posterior coxse of both sexes; sternum 

 broadly triangular, sides rounded, obtusely pointed behind. The region of 

 the epigynum projects ljelo\A' the venter, showing behind a transverse region 

 rounded on sides and slightly divided in the middle. Tlie male palpi are very 

 long, the femur being nearly as long as the breadth of the cephalotliorax, cyl- 

 indrical and with a minute spine at extreme base; patella about one-half as 

 long, gradually enlarged to tip, and with a small si^ine at base; tibia very 

 short, but with a very long slender hook which is strongly curved toward tip; 

 the tarsus is broadly triangular, above with a blunt projection at tlie angle 

 A^ here it touches the tiljial liook, the bulb has a very long, tapering stylus of 

 about five gi-adually enlarging coils. 



Fort Collins, some under a board, others among dead leaves. 



The genus Tiso is related to Erigone, but it differs in the 

 structure of the S palpus and in the w^eaker mandibles. In the 

 European species the $ head is not elevated, but in this and in 

 an allied species from Washington the head is distiucth' elevated. 



Linyphia clathrata Koch. 

 Fort Collins (Gillette). 



Linyphia orophila Tlior. 



Gray's Peak, July (Packard). 



