22 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. IO3 



For the larval stages, Dermestes caninus Germ., Dermestidae, and 

 Tenebriodes sp., Ostomatidae, were chosen for study. 



In Dermestes (figs. 84, 85, 86) the labral muscles are absent; the 

 dorsal dilator muscle of the cibarhim, 5, the dorsal dilator muscle of 

 the pharynx, 11, and the compressor muscle group of the cibarium, 

 12, are also absent. The other cibarial, pharyngeal, and hypopharyn- 

 geal muscles are present and well developed. The muscle of hypo- 

 pharyngeal bar Y, 10 (figs. 84, 85), is branched and especially mas- 

 sive. Bar Y (fig. 84) is heavily sclerotized and forms a rigid lateral 

 support to the dorsal cibarial region and to the mouth. As is the 

 case in the adult Dermestes, the labial muscle, 21 (figs. 84, 86), is 

 difficult to homologize with those of the generalized form ; the selec- 

 tion of their numerical designations (names), in this case, is influ- 

 enced entirely by their points of insertion. 



In Tenebriodes sp. the ventral muscle of the labrum, j, is present. 

 The cibarial, pharyngeal, hypopharyngeal, and labial muscles are simi- 

 lar to those of Dermestes; the ventral muscle of the labium, 21, arises 

 on the tentorial structure and not on the submentum as it does in 

 Dermestes. 



XV. MELOIDEA 



Macrobasis immaculata (Say), Meloidae (figs. 87, 88, 89), is the 

 adult studied in this super family. The labral muscles, i and j (figs. 

 87, 88), are present and well developed. The dorsal dilator of the 

 cibarium, 5, is absent ; the compressor muscle group of the cibarium, 

 12, is weak; the other cibarial and pharyngeal muscles are strong. 

 The proximal (ventral) region of bar Y (fig. 88) supports the ven- 

 tral pharyngeal wall and the sides of the mouth. In the labium the 

 levator muscle of the labial palpus, 24 (figs. 88, 89), takes its origin 

 on the intralabial sclerotized bar, IR (fig. 88), that terminates later- 

 ally in a broad lateral hypopharyngeal sclerite. The muscle of the 

 hypopharynx, ip (figs. 88, 89), arises in the usual area and is in- 

 serted medially on a short apodeme process by means of a tendon. 



The larva studied is Zonabris phalerata (Pall.) (figs. 90, 91, 92). 

 The muscles are well developed in this species, though the compressor 

 muscle of the labrum, i, and the dorsal dilator muscle of the cibarium, 

 5, are absent. The dorsal muscle of the labium, 20 (figs. 91, 92), 

 arises in the posterior region of the submentum and the ventral muscle 

 of the labium, 21 (figs. 91, 92), originates medially in the anterior 

 region. Hypopharyngeal bar Y (fig. 91) is continuous with a long 

 sclerotized subpharyngeal structure that joins the two bars together 

 in the posterior region of the ventral wall of the cibarium. 



