LARVAL FORMS OF C0LE0PTP:RA 



clistiiigTiished by the same characters by which the series is defined 

 and in addition by the following characters: Labrum elono'ate, 

 conical, fitting- into a groove on the dorsal side of the mandibles; 

 molar strnctnre of mandible ])resent but rather indistinct ; maxil- 

 lary articulating area well-developed; maxillary palpus three- 

 jointed, palpiger excluded ; cardo bipartite ; ligula large and broad ; 

 prothorax hood-shaped, somewhat swollen dorsally and ventrally; 

 ninth abdominal segment terminal and heavily sclerotized ; spiracles 

 bilabiate. 



Key to Subfamilies 



1. Ninth abdominal segment cylindrical, obliquely truncate pos- 

 teriorly, armed with a raised rim and with rugosities or 

 tubercles on the disk inside of the rim ; abdominal epipleural 

 lobes with a hard, tubercled or shagreened surface 



Lymexylidae -Lymexylinae 

 ( Melittomma a u d Atracto- 

 cerus) (pi. 124 A-G, J-K, M) 

 Xinth abominal segment elongate conical, thorn-shaped, termi- 

 nally with upward bent, bicuspidate apex; epipleural lobes 

 glabrous. (First larval instar with a more disklike ninth 



abdominal segment) L y m exy I i d a e - Hi/lecoetinae 



{HylecoeUis) (pi. 124 H, L) 



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