346 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 37 



of the 3d sclerite (Maki), pleural muscle of the 3d axillary sclerite 

 (Bonhag), muscles of 3d axillary (Miller in Demerec). 



This muscle has three branches. The largest branch (9, b, i) origi- 

 nates on the episternum, the origin being much occluded by the axil- 

 lary muscle of the ist sclerite (9, a, i). A branch of about the same 

 dimensions (9, b, ii) has its origin on the posterior side of the pleural 

 sulcus. The third branch, not shown in figure 4, is a snmll slip of 

 muscle arising on the dorsal part of the pleural sulcus. 



c. Axillary mtcscle of 4th sclerite. 



There are two branches of this muscle ; they are better considered 

 separately. The weak sclerotization of the region of their insertion in 

 Anisopus has made their precise determination difficult and perhaps 

 uncertain. 



i. AXILLARY MUSCLE OF 4TH SCLERITE — PLEUROSULCAL BRANCH. 



Other names are : Possibly tergopleural muscle "4B" (Snodgrass), 

 2d supinator (Ritter), ist tergopleural (pleuroaxillary) muscle of 

 4th axillary sclerite (Maki), pleural muscle of 4th axillary (Bon- 

 hag), and possibly muscles of 4th axillary (sclerite) or axillary cord 

 (Miller in Demerec). 



This muscle has already been mentioned under 7, c, above. It origi- 

 nates on the pleural sulcus above the point where the sulcus meets the 

 dividing line between the episternum and the sternopleuron. 



ii. AXILLARY MUSCLE OF 4TH SCLERITE — EPIMERAL BRANCH. 



Other names are: Adductor of the wing ("adductor alae") (Rit- 

 ter), 2d tergopleural muscle (pleuroaxillary) of the 4th sclerite 

 (Maki), possibly the pleural muscle of the posterior notal wing 

 process (Bonhag), subalar muscle (Miller in Demerec). 



Maki (1938), dealing with Orthellia (Muscidae), and Bonhag 

 (1949), dealing with Tabaniis (Tabanidae), have indicated a multi- 

 branched muscle in the position of this muscle, though the latter 

 gave its insertion as on the posterior notal wing process. Maki (1938) 

 indicates only a single muscle here in a tipulid. It originates on the 

 epimeron. I consider that this may be the muscle identified by 

 Snodgrass (1935) and Miller in Demerec (1950) as a subalar muscle, 

 the former assuming that its origin had migrated from the meron to 

 the epimeron in the "higher Diptera"; this matter is discussed else- 

 v/here in this paper. 



