2 W. Dwight Pierce 



Neb., for valuable advice and information. Mr. Crawford 

 and Mr. Swenk have both furnished lists. of bees that visit certain 

 host plants and those that might be implicated in other ways. 

 Mr. Crawford has also furnished specimens and determinations, 

 in addition to assisting- in deciphering several of the problems. 

 Acknowledgments are also due to various members of the Uni- 

 versity Studies committee for aiding toward a concise state- 

 ment of the facts embodied. 



Part I 



THE HYPERMETAMORPIIIC BEETLES 



Under this grouping we place those three families of Hetero- 

 mera, Meloidae, Rhipiphoridae, and Stylopidae, which undergo 

 hypermetamorphosis and are parasitic in the larva form at least. 



Heteromera is defined by Le Conte as having the front and 

 middle tarsi 5-, and hind tarsi 4-jointed. In Stylopidae will be 

 found exceptions to this rule which the author thinks, however, 

 due to parasitism. Their natural position is assuredly with the 

 three above named families. Heteromera is first divided as to 

 whether the coxal cavities are closed or open behind. The fam- 

 ilies under consideration have them open. 



The next division is as to the constriction of the head at its 

 base. The families Monommidae, Melandryidae, Pythidae, and 

 Oedemeridae do not have the head strongly and suddenly con- 

 stricted at the base. The remainder of the families have the 

 head strongly constricted at the base. The Cephaloidae have 

 the head prolonged behind and gradually narrowed. 



Mordellidae have the lateral suture of the thorax distinct ; this 

 is also true of the Evaniocerini in the Rhipiphoridae. The other 

 families lack the lateral suture. In Mordellidae the antennae 

 are filiform, n-jointed, and usually slightly thickened externally, 

 and the elytra are narrowed behind, exposing the tip of the 

 abdomen, though not truncate. 



Anthicidae have the hind coxae not prominent ; the antennae 

 Ii-jointed, nearly filiform, and rarely Ilabellate. 



154 



