18 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 134 
and with the sternal coxal articulation of the thorax at the basal por- 
tion of the outer and inner surfaces, respectively. The basal end of 
the coxa is girdled by a submarginal basicostal suture (bes), which 
forms internally a submarginal basicostal ridge and sets off a narrow 
marginal flange, the basicoxite (bex), which is enlarged on the outer 
surface posterior to the pleural articulation. 
The TROCHANTER (tr) is a rather small segment that is proximally 
constricted. This gives it a superficially 2-segmented appearance. Its 
distal end is obliquely truncate with the concave dorsal surface shorter 
than the convex ventral surface. It is attached proximally to the coxa 
by a membrane and articulates with the coxa by an anterior and a 
posterior condyle. The deeply emarginate dorsal margin of the coxa 
allows for a wide range of motion of the leg on this dicondylic hinge. 
A dicondylic hinge is present at the distal end of the trochanter also. 
This operates at a right angle to the coxotrochanteral hinge but per- 
mits of much less freedom than the latter since nearly the entire distal 
rim of the trochanter is closely adjacent to the end of the femur. 
The FEMUR (fe) is the second longest segment of the leg. It is 
nearly cylindrical and armed with numerous spines and setae, espe- 
cially on its dorsal and ventral surfaces. In addition, the posterior 
surface of the prothoracic femur, the anterior and posterior surfaces 
of the mesothoracic femur, and the anterior surface of the hind femur 
are also provided with numerous setae and spines. This is evidently 
correlated with the natural position of the legs; forelegs held anteri- 
orly, middle legs held posterolaterally, and hind legs held posteriorly. 
The distal margin of the femur is crowned with several short spines. 
The Trp1a (tb) is the longest segment of the leg, nearly cylindrical, 
and rather slender. Its proximal end is bent toward the femur, allow- 
ing the tibia to be flexed close against the undersurface of the femur. 
The tibia articulates with the femur by a dicondylic hinge. Numerous 
medium to long spines and setae are borne on both the dorsal and 
ventral tibial surfaces, the heaviest spines being present on the ventral 
surface close to the distal margin. In addition, there are many short 
spines scattered generally over the entire surface. 
The Tarsus (ts) is 3-segmented. The basal segment or basitarsus 
is the second longest tarsal segment. It is slightly bent near its distal 
end and can be flexed against the tibia. The second tarsomere is only 
slightly shorter than the basitarsus. It is obliquely truncate distally 
so that its dorsal surface is shorter than the ventral surface. The third 
tarsomere, or distitarsus (dts), is the longest of the three tarsal seg- 
ments. It bears a ventrodistal projection, the plantella (pt), which is 
