4 Introduction 



Forbes reached a similar result from his studies of the wings. 

 "Ochthebius and Hydrnpna," he says, "do not belong here (in 

 Hydrophilidae) , but with the aberrant "Silphidse;" and the latter he 

 classifies ■with his Staphyliniformia. 



It should be noted that within the families Anisotomidse and 

 Staphylinida", the larval characters indicate many subfamilies, with 

 Ox}T)orina^, Habrocerinte, and others, quite definitely separated ; and 

 that the Histeridje, on larval characters, are associated with 

 Hydrophiloidea, a view in which apparently Forbes' conclusions 

 are not entirely in accord. 



Hydrophiloidea. In this superfamily Dr. Boving groups Histeridae 

 and Helophoridfe, "on account of an unquestionable conformity'' in 

 the development of the fundamental systematic characters" of their 

 larvjc; Spereheidae; Hydrochidae and Hydrophilidae, the latter 

 divided into subfamilies Berosinae, Hydrophilinae, Hydrobiinae, and 

 Sphaeridiinas. The treatment of Histeridae, regarded by Forbes as a 

 superfamily, and by Tillyard as "very distinct and isolated," is at 

 first sight rather startling; but it is to be noted that Forbes also 

 found that the venational characters seemed "to link Avith the 

 Hydrophilidae on one side and more closely to the Lamellicornia on 

 the other." The views of Tillyard regarding Hydrophiloidea as 

 "perhaps the oldest of existing Coleopterous groups" traceable "back 

 geologically to the upper Permian" are interesting. He further says 

 "the fossil evidence, so far as at present available, Avould tend to 

 indicate that. . . .the development of longitudinal striae and intervals 

 is an entirely new formation. If this be so, the almost smooth elytra 

 of many Hydrophilidae probably represent the most primitive tj^pe." 

 The same argument would apply to the comparatively smooth elytra 

 of the Histeridas, and thereby support Dr. Boving 's classification of 

 the larvae. Moreover, while Hololepta and Hydrophilus in the adult 

 stage seem far apart, some of the small Saprini are not so dissimilar 

 to the Sphaeridiinae. 



Cucujoidea. Dr. Boving finds three types of larvae in the Poly- 

 phaga. The primitive type is found in its most characteristic and 

 original form in such families as the Limnebiidae, Leptinidae, and 

 Anisotomidfe. From it are derived the more or less specialized larvae 

 of the Staphylinoidea and Hydrophiloidea, which have therefore 

 preceded other Polyphaga in his conspectus. 



A distinct poh^jhagous larval type is found in the series 

 Cucujoidea. It shows such close affinities Avith the staphylinoid- 

 leptinid tji^e as to be placed next thereto in the conspectus. The 

 families included are (semi-colons indicating their grouping) 

 EucinetidfB, Derodontidfe, Monotomidae, Khizophagidae ; LanguriidcB, 

 Cryptophagidae, Silvanidce, Cucujidae, Prostomidce; Catofjenidce, 

 LcemophloeidcB, Phalaeridae, Smicripidce, Corylophidae ; Nitidulidae, 

 Cyhocephalidce; Sphindidae; Lathridiidae, Murmidiidae, Endomy- 



