]^78 PROCEEDINGS OF THE NATIONAL MUSEUM vOL. 106 



Description : Size : Length, 400 to 455 ; width, 245 to 285. 



Shape: Ovoid. 



Color: Yellow (Brennan, 1948). 



Gnathosoma: Seta on palpal femur strong, curved, moderately 

 clothed with setules. Seta on genu smaller, pectinate. Dorsal seta 

 on tibia pectinate ; lateral seta on tibia slender, with one or two 

 slender setules, or nude; ventral seta slender, with about three 

 alternate rows of setules on the dorsal side of the shaft. Palpal 

 claw curved, with three prongs, median prong longest. One speci- 

 men with five prongs on the palpal claw. Galeal seta v/ith several 

 setules. Cheliceral base typical; blade strong, curved, subapical 

 dorsal and ventral teeth distinct. Palpal coxa punctate; base of 

 chelicera indistinctly punctate. 



Legs : Leg I with two genualae, a microgenuala, two tibialae, a 

 microtibiala, a middorsal spur and a distal microspur, a subterm- 

 inala, a parasubterminala, and a pretarsala, all rather short. Leg 

 II with a genuala and two tibialae, all very short ; spur long with 

 microspur anterior to it; pretarsala of normal size. Leg III with 

 a very small genuala; no tibiala. Nonspecialized setae on leg I 

 generally with a fringe of short, curved setules; nonspecialized 

 setae on legs II and III mostly with fewer and straighter setules. 

 All coxae punctate ; some distal segments punctate. 



Anomaly: Both subterminalae I and both parasubterminalae I 

 lacking in one specimen. 



Scutum : Over twice as wide as long. Anterior margin slightly 

 concave between anteromedian seta and anterolaterals. Lateral 

 margins concave, diverging posteriorly. Posterior margin convex 

 posterior to pseudostigmata, usually slightly concave between 

 them; exact outline som.ewhat obscured by cuticular striae. An- 

 teromedian seta close to the anterior margin. Setae rather short, 

 covered with short setules. Pseudostigmata a moderate distance 

 apart ; posterior to a line drawn between the posterolateral setae ; 

 deep, in marked depressions under the medial margins of strong 

 horseshoe-shaped ridges. Sensillae long clavate; each enlarging 

 from the base without distinct pedicel; widest about four-fifths 

 the length from the base; covered by setules which extend down 

 to the pseudostigma ; setules longer and smoother on the anterior 

 surface. Surface of scutum with punctae, usually most apparent 

 m medial region, usually one or two larger pits or pores near 

 ridge medial to posterolateral setae. Cuticular striae encroach 

 upon the posterior margin and appear to cross the anterolateral 

 corners posterior to the anterolateral setae. 



Summary of standard data of four specimens from Beaverhead 

 County, Mont. (AM's from two specimens, S's from three) : 



