16 PROCEEDINGS OF THE NATIONAL MUSEUM vol.75 



dark ochreoiis ventrally; dorsal and ventral sclerites well defined. 

 Setae long, strong, and many of the dorsal ones slightly enlarged at 

 the end, a development not noticed in the other investigated Trir- 

 habda larvae, in all of which the setae are pointed. 



GALERUCELLA NYMPHAEAE Linnaeus * 



(U. S. Nat. Mus. ; described from larva iu vial marked: "Craighead, Penn- 

 sylvania, July 4, 1921, E. M. Craigliead Coll."') Reared. 



Mature larva (fig. 18).— About 10 mm. long. 



Head smooth and shining, either entirely black or with reddish- 

 brown anterior margin; labrum cream colored with dark posterior 

 corners; coronal ( = median epicranial) and frontal sutures appearing 

 as fine white lines. Body with membranous parts greenish-gray; 

 prothoracic shield, dorsal sclerites and pygidial shield shining, dark 

 chestnut brown; all three thoracic segments with a whitish sagittal 

 suture; dorsal sclerites coarsely corrugated and covering almost the 

 entire upper side of the body, skin between the sclerites appearing 

 only as light lines ; pygidial shield variolose, irregularly and coarsely 

 corrugated and uniformly colored ; underside of body light greenish- 

 gray with sclerites small and light ochreous. Legs blackish brown 

 on the exterior side, ochreous on the inner side. 



Setae short, thin, and pointed (fig. IT) ; most sclerites with few 

 minute spinulae. 



Head capsule. — With an unpaired shallow anterior depression be- 

 hind epistomal margin; a small grain-shaped elevation on each side 

 in the posterior corner of f rons. 



Labrum (fig. 16). — About twice as wide as long; anterior margin 

 forming an arch of about 120°. Discal setae rather short, straight, 

 and pointed; marginal setae short, curved, and pointed. 



Mandible (fig. 19). — ^With five teeth; inner margin behind the last 

 tooth somewhat incurved ; first tooth small and narrow, second, third, 

 and fourth larger, all pointed and claw shaped; fourth and fifth 

 completely separated; fifth short and broad, penicillus present; two 

 short setae located externally. 



Maxilla (fig. 20) . — ^With lacinia distally pectinate, carrying a row 

 of about 10 subcylindrical, distally obtuse, strong, and long setae, all 

 of same length and build; galea armed with six spinelike setae of 

 moderate length, between these a short, cone-shaped tactile appendix ; 

 maxillary palpus with only three joints, basal joint (often referred 

 to in the literature as "palpiger") characterized by two long setae; 

 the virtual palpiger soft, light colored, without individual muscles, 

 and located distally to the chitinized stipes. 



Postl<ihial band. — Medianly somewhat forward curved, laterally 

 strongly rounded. 



