36 Annals Entomological Society of America [Vol. XIII, 



The Anterior Flexor of the Femur (Fig. 26, ant. fl.) is a broad 

 flat muscle with parallel fibres. It originates from the basal 

 edge of the anterior face of the trochanter and is inserted into 

 the anterior face of the femur. These two muscles are not 

 present in the small trochanter of the hind legs. 



(c) Femoro-tibial Muscles. 



The Extensor of the Tibia (Figs. 23 and 25, ext. tib.) In the 

 large leaping hind leg this muscle originates from the entire 

 dorsal two-thirds of the inner surface of the femur. It is a 

 pseudo-penniform muscle sending short oblique fibres into the 

 long spatulate tendon by which it is inserted into the dorsal 

 edge of the base of the tibia. 



In the first and second legs (Fig. 25, ext. tib.) the extensor 

 is much weaker. The tendon is shorter and the fibres originate 

 chiefly from the basal end of the femur, though some spring 

 from near or beyond the middle of the segment. 



The Flexor of the Tibia (Figs. 23 and 25, fl. tib.) originates by 

 two heads from (1) the ventral side of the base of the trochanter 

 and (2) the proximal end of the ventral side of the femur. It 

 is a conical muscle and is inserted into the ventral proximal edge 

 of the tibia by means of a long linear tendon. 



(c) Tibio-tarsal Muscles. 



The First Extensor of the Tarsus (Fig. 23, 1 ext. tar.) is very 

 similar to the extensor of the tibia in the hind leg. It lies in the 

 ventral half of the tibia, and is inserted into the proximal end 

 of the first tarsal segment. 



The Second Extensor of the Tarsus (Fig. 23, 2 ext. tar.) 

 originates from the dorsal side of the tibia near the femoro- 

 tibial articulation. It is a short conical muscle and is inserted 

 by a long filamentous tendon, running through the greater part 

 of the tibia and tarsus, into the ventral edge of the third tarsal 

 segment. 



The second tarsal segment, projecting as it does backwards 

 and forwards beneath the first and third, Hmits the flexing of 

 the tarsal segments, so that this muscle extends the entire 

 tarsus outwards in a straight line with the tibia. 



The Flexor of the Tarsus (Fig. 23, fl. tar.) originates in the 

 dorsal face of the tibia a short distance from the articulation 

 with the femur. It is inserted by a flat tendon into the first 

 tarsal segment. 



