NO. 7 MUSCULATURE OF COLEOPTERA DORSEY 2$ 



(figs. 103, 104), are all well developed and conform rather closely 

 to the generalized plan of musculature. 



XVIII. BOSTRICHOIDEA 



Apatides fortis (Lee), Bostrichidae, adult and immature forms, 

 were used for study in this superfamily. 



In the adult Apatides (figs. 105, 106, 107) the epipharynx is large 

 and conelike; the compressor niiiscle of the lahniui, i (fig. 106), is 

 elongate and is inserted laterally near the tip of the epipharynx. The 

 epipharynx (fig. 106, EP) is supported laterally by a slender sclero- 

 tized rod {SR) arising dorsally on a tormalike process that extends 

 mesad from the side of the labrum anterior to the base of the normal 

 torma. The ventral muscle of the labrum, j (figs. 105, 106), is in- 

 serted on the distal end of the torma which is more elongate than 

 usual. The cibarial, pharyngeal, and hypopharyngeal muscles are 

 strong. The dorsal dilator muscle of the ciharium, 7 (figs. 105, 106), 

 apparently has a branch, yA (fig. 105), the point of origin of which 

 has migrated anteriorly to the posterior surface of the epistomal 

 suture. The labial muscles are well developed ; the ventral muscle of 

 the labium, 21 (figs. 106, 107), possibly in reality is the muscle of 

 the prementum, 22, since it takes its origin laterally in the posterior 

 region of the submentum. 



The larval Apatides (figs. 108, 109, no) exhibits the first labral 

 compressor muscle, i (figs. 108, 109), observed in immature Coleop- 

 tera. The powerful ventral muscle of the labrum, j (figs. 108, 109), 

 is inserted on the distal end of an elongate torma ; the muscle of hypo- 

 pharyngeal bar Y, 10 and loA (fig. 108), is branched and strong. 

 The ventral and lateral dilator muscles of tlie pharynx, jo and ji 

 (fig. 108), are especially well developed. In the labium the dorsal 

 and ventral labial muscles, 20 and 21 (figs. 108, no), lie so close 

 together that superficially they appear to be one muscle. The unusual 

 muscle 41 (figs. 108, no) was observed only in this species; it arises 

 laterally in the anterior region of the submentum and extends dorsally 

 almost vertically to become inserted laterally at the base of the 

 labium near the dorsal surface. 



XIX. CHRYSOMELOIDEA 



Leptinotarsa decimlineata (Say), Chrysomelidae, Donacia distincta 

 Lee, Donaciidae, and Galerucella xanthomelaena (Schr.), Galeru- 

 cidae, are the specimens of adults studied in this superfamily. 



In Leptinotarsa (figs, in, 112, 113) the muscles of the dorsal 

 head region are well developed. The muscle of hypopharyngeal bar Y, 



