NO. 2 THORACIC MECHANISM OF A GRASSHOPPER — SNODGRASS 



71 



(fig. 39 A, ijjAp) arising from dorsal margin of base of tibia. On 

 the base of this apodeme are inserted two short, strap-like branches 

 (fig. 36 F, 133c, I35d) arising dorsally in distal part of femur. 



136. Depressor of the tibia (fig. 39). — A relatively small muscle 

 with long, slender fibers {136a) arising in ventral part of femur and 

 converging to sides of long, tapering apodeme arising in ventral mem- 

 brane of knee joint. The terminal, strap-like part of this apodeme 

 slides over a strong, internal process (a) of ventral wall of femur. 



135b 



136 a 



135c 135At 



Tn 



Fig. 39. — Musculature of the hind leg of Dissosteira. 



A, left leg, anterior (outer) view. B, cross-section through basal half of left 

 femur, proximal end of distal piece, showing positions of levator and depressor 

 muscles of tibia and of principal tracheae. 



Two small, anterior and posterior bands of fibers, arising on dorsal 

 wall of femur, are inserted on apodeme near its base, the anterior one 

 {136b) shown in the figure. 



137. Levator of the tarsus (fig. 39). — A very small dorsal muscle 

 in distal end of tibia, inserted on dorsal rim of base of tarsus. 



138. Depressor of the tarsus (fig. 39). — A small muscle, but longer 

 than the levator, arising ventrally in distal part of tibia, inserted on 

 ventral lip of base of tarsus, 



i3p. Depressor of the pretarsiis: retractor of the clazvs (fig. 39). — 

 Comprises three small groups of fibers, one arising posteriorly in ven- 

 tral part of femur among fibers of tibial depressor, the second {139b) 



