38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 94 



the coxa. The trochanter articulates with the coxa by means of two 

 rather indefinite condyles (a, c, and a, a) which permit a dorsoventral 

 movement only. The distal two-thirds of the exposed surface bears 

 numerous moderately long setae, and the area at s (fig. 8 G) has a 

 very few large pores which are quite distinct from the setigerous 

 punctures. 



The femur (fig. 8F) is the largest segment of the leg. It tapers 

 somewhat distad and bears a large tubercle on its ventral proximal 

 margin. The proximal end is obliquely truncated and is immovably 

 united to the trochanter by a flat surface. The distal end bears a dorso- 

 ventral groove in which the tibia articulates. This groove is known 

 as the gonytheca (gony). The proximal dorsal tip forms an acutely 

 rounded projection which appears to articulate to some extent with 

 a socket on the outer edge of the coxa. The posterior surface of the 

 femur is moderately densely set with setae, more sparsely proximad 

 and dorsad. The setae of the anterior surface are similarly arranged, 

 being very dense along the tubercle, very sparse on the basal dorsal 

 part, and entirely lacking from a narrow strip along the ventral face, 

 which is outlined on both the anterior and posterior faces by an ir- 

 regular longitudinal series of more closely placed setae. Another series, 

 of more widely spaced setae, extends along the dorsal face into two 

 smooth areas. The setae are somewhat longer and more dense near 

 the dorsal apical margin and show some tendency to serial arrange- 

 ment across the tip. With transmitted light one may observe the 

 minute pores which occur in clusters of two to five about the base of 

 each seta. The surface is extremely finely and irregularly, but linearly 

 and longitudinally, striate in great part. 



The tibia is the fourth segment of the leg. In the prothoracic leg 

 (fig. 8 F, tb) it is shorter than the femur and about one-half as thick, 

 expanding slightly toward the apex. It articulates with the femur 

 by means of a rounded head on its proximal end, which fits into the 

 groove or gonytheca of the femur (gony) and is held there by a pair 

 of condyles on each side. This head is somewhat curved toward the 

 femur, allowing the tibia to lie along the ventral edge of the femur 

 at rest. The distal end of the tibia is rather rounded and membranous. 

 It bears the tarsus and the two tibial spurs as well as numerous very 

 stout heavy setae around the tip. The spurs are known as the calcaria 

 (cal). They are inserted within the membranous area of the tip, but 

 are apparently merely slightly modified setae. The larger one is in- 

 serted on the posterior side of the tarsus and the smaller one on 

 the anterior side, both of them slightly ventrad of the middle. The tip 

 is nearly circled by two series of very large and heavy setae, one on 



