1920] Dii Porte: Muscular System of Gryllus 29 



STERNAL MUSCLES. 



(a) Sterno-pedal. 



28. The First Pedal Muscle of the Prothorax (Fig. 21). 

 From the base of the furca into the anterior border of the 

 coxa. Extensor of coxa. [127]. 



29. The Second Pedal Muscle (Fig. 20). . From the furca 

 near its base into the posterior border of the coxa. Flexor of 

 the coxa. [128]. 



30. The Third Pedal Muscle (Fig. 21). From the furca 

 above the leg cavity into the meso-caudal edge of the coxa. 

 An adductor and flexor of the coxa. [129]. 



31. The Seventh Pedal Muscle (Fig. 21). From the spira 

 into the posterior border of the coxa. Probably a weak flexor 

 or rotator, but of little functional importance. [131]. 



B. The Mesothorax. 



LONGITUDINAL MUSCLES. 



(a) Sternal. 



32. The Second Mesosternal Muscle (Fig. 21). Homologue 

 of 14. [66]. 



33. The Third Mesosternal (Fig. 20). Homologue of 15. 

 [67]. 



34. The Fourth Prosternal (Fig. 20). Homologue of 16. 

 [68]. 



(b) Dorsal. 



35. The First Mesonotal Muscle (Fig. 21). A broad flat 

 muscle near the dorsal median line originating from the ento- 

 tergite of the metathorax^ and inserted into the anterior border 

 of the mesoscutum. This and the next are retractors of the 

 thorax drawing the meso- and meta-tergites together. [69]. 



36. The Second Mesonotal (Fig. 20). Similar to 35 in 

 origin, but inserted into the first intersegmental sclerite. Lies 

 on the inner (ventral) side of 35. [70]. 



XXXVI. The Third Mesonotal (Fig. 21). An oblique 

 muscle running from the second intersegmental sclerite to the- 

 mesoscutellum. [71]. 



