MUSCULATURE OF DIPTERA — SMART 349 



trochanter muscle in Drosophila. A sternal depressor of the tro- 

 chanter, with its origin on the furca, was reported present by Maki 

 (1938) in all five of the Diptera examined by him; Bonhag (1949) 

 also found a sternal depressor muscle of the trochanter in Tabamis. 

 I find that in the specimens of Drosophila melanogaster available to 

 me a sternal depressor of the trochanter with origin on the underside 

 of the cups of the furca is present and joins the tergal depressor on 

 the trochanter. It seems possible that Miller in Demerec mistook this 

 muscle for the one which he calls a "sternal remotor" of second coxa 

 (his "65"). 



13. COXAL TROCHANTERAL LEG MUSCLES (PL. I, FIG. o). 



Five muscles in the mesothorax of Anisopus can be assigned to 

 this group. Maki (1938) and Ritter (1911) did not consider the 

 muscles of this group. 



a. 1st anterior levator of trochanter. 



Other names are: Levator of trochanter (Snodgrass), branch of 

 dorsal levator of trochanter (Bonhag), levator of trochanter (Mil- 

 ler in Demerec). 



Originates on both the ventral parts of the pleural sulcus and on 

 the coxa below the now almost immobilized articulation of the latter 

 with the former. 



It is, however, a single muscle and undoubtedly acts as a levator of 

 the trochanter along with E, 13, b; both insert together on the an- 

 terior rim of the trochanter distal to the coxotrochanteral articulation. 



Maki (1938) reported a pleural depressor of the trochanter in a 

 tipulid. I suspect that he misidentified this muscle as such. 



Miller in Demerec (1950) mentions only one levator in Drosophila. 



b. 2d anterior levator of trochanter. 



Other names are: Levator of trochanter (Snodgrass), branch of 

 dorsal levator of trochanter (Bonhag). 



Originates on the anterior rim of the coxa and inserts along with 

 E, 13, a, on the anterior rim of the trochanter distal to the coxotro- 

 chanteral articulation and acts as a levator. 



c Posterior levator of trochanter. 



Other names are: Levator of the trochanter (Snodgrass), ventral 

 levator of trochanter (Bonhag). 



