NO. 2 HONEY BEE SNODGRASS IO3 



J7. Compressors of the suctorimn (fig. lo C). — Five thick bundles 

 of fibers on anterior wall of cibarial region of sucking pump, the 

 first transverse over the mouth, the others oblique between the dilators, 

 attached laterally on oral plate (opl). 



J2. Protractor of the oral plate (fig. lo B, C). — Origin ventrally 

 on a process of frontal aspect of base of anterior tentorial arm, in- 

 sertion dorsally on upper part of pharyngeal arm (y) of oral plate 

 above frontal ganglion connective. (Lateral pharyngeal muscle 

 Duncan.) 



jj. Retractor of the oral plate (fig. lo B, C). — A smaller muscle 

 than the last arising medially on frons below median ocellus, inserted 

 ventrally opposite J2 on arm of oral plate. (No corresponding muscle 

 given by Duncan in the wasp.) 



J4, j5. Precerebral dilators of the pharynx (fig. loC). — Two 

 small muscles arising on frons, inserted on pharyngeal region of suck- 

 ing pump just above frontal ganglion. (Frontal dilators of the anterior 

 pharynx Duncan.) 



5(5. Postcerebral muscle of the pJmrynx (fig. lo C). — Long slender 

 muscle arising on vertex, inserted laterally on upper extremity of 

 pharynx, probably mainly suspensory in function. (Dorsal dilator of 

 the posterior, pharynx Duncan.) 



J/. Posterior contractor of the pharynx (fig. loC). — A long, 

 median, fusiform muscle lying against posterior wall of pharynx, aris- 

 ing by slender tendon on median process of tentorial bridge, inserted 

 ventrally on inner edge of oral plate. (Posterior dilator of the anterior 

 pharynx Duncan.) 



j8. Parietal contractor of the pharynx (fig. lo C). — A broad sheet 

 of fibers spreading over lateral and posterior walls of pharynx from 

 two points of origin laterally on tentorial bridge, fibers going beneath 

 circular muscles on lower half of pharynx to attachments on arms 

 of oral plate. This muscle and the last are termed "dilators" of the 

 pharynx in the wasp by Duncan, but their lengthwise distribution 

 would suggest that they are contractors of the pharynx, though at the 

 same time they may dilate the cibarium. 



5p. Constrictors of the pharynx (fig. lO C). — The layer of circular 

 fibers investing the entire pharyngeal region of the sucking pump, 

 continued on the oesophagus. 



40. Superior phragmatic levator of the head (fig. 12 A). — One of 

 a pair of submedian, parallel muscles arising on prephragma of meso- 

 notum, inserted laterally on dorsal margin of foramen magnum. 

 (Levator capitis horizontalis Morison.) ' 



