NO. 12 



FLYING APPARATUS OF BLOW-FLY — RITTER 



25 



somewliat thickened edge of tlie parapleurum and passes into a 

 long, delicate tendon which is attached to the processus duplicatus 

 of pterale A. 



4. TJic levator alcr sccundus (text fig. 6, pi. it, fig. 30, pi. 13, 

 fig. 34; mell). This nin.scle is rhombic in shape. It arises close 

 to the mesapodema, at the boundary between the parapleurum and 

 the mesosternum, and passes into a strong tendon which follows 

 the episternal border alongside the supinator; apparently united 

 with the tendon of that muscle, it passes to the foramen priealare. 



p t IV p d 



m b II 



m e 



Fig. 6. Diagrammatic view of the direct muscles that lie nearer the median 

 plane. (Median section of the thorax.) 



a, Mesapodema. 



ap, Mesapophysis. 



HI, Musculus latus. 



ma, Musculus anonymus. 



mbl, Musculus abductor alse primus. 



mbll, Musculus abductor alae secundus. 



mel, Musculus levator ate primus. 



mell, Musculus levator ate secundus. 



md, Musculus adductor ate. 



me, Musculus gracilis. 



nip, Musculus pronator ate. 



0, Foramen praealare. 



Oi, Foramen postalare. 



pd, Processus dactyloformis. 



pe, Pareposternum. 



pti, Processus pteralis thoracis I. 



ptil, Processus pteralis thoracis II. 



ptIV, Processus pteralis thoracis IV. 



ptA, Pterale A. 



St, Stigma anterius. 



sti, Stigma posterius. 



There its tendon is joined to the processus duplicatus of pterale A, 

 while the tendon of the supinator alse passes into the ligamentum 

 anale. 



