wa 
J 
940 On the Genealogy of the Insects. [September, 
Dytiscidæ (and Hydradephaga in general).— Maxilla with the 
mala absent; the palpi four-jointed. 5 
The maxilla in the aquatic forms of the Carabid type is only a — 
modification of the Geodephagous maxilla; the terminal palpal 
joint being acute and raptorial. er 
Staphylinide —Maxilla with a one-jointed inner lobe (Xantho 
linus), or the mala broad and setose as in the succeeding families — 
(Platystethus and especially Bledius); maxillary palpi three and 
four-jointed. a 
The Staphylinid type of maxilla is simply a modification of 
the Carabid, with a tendency to degeneration in the own 
genera (Bledius, etc.). Many larve in this family are car 
nivorous. 
Elateride.—Maxilla with a two-jointed lobe or mala; the max 
illary palpus four-jointed. Antennæ four-jointed, bifurcate as 10 
Carabid larvæ; mandibles toothed. The larvæ of Elater and 
Athous are free. While generally supposed to be vegetable 
eaters (as Agriotes), those larvæ which live under the bark | 
trees in mines made by longicorns and other borers, have been : 
shown by Ratzeburg, Dufour and Perris to be in part carnivor: 
ous, living on Dipterous and longicorn larvæ, as well as OF 
excrementitious vegetable matter filling the burrows. P eren £ : 
sectes du Pin Maritime, p. 190) has pointed out the close ar : 
blance of the mouth-parts of this family to those of the : 
Carabide. ae 
going families; the maxillary lobe, or mala, being me 
derma), and in Pyrochroa, which is carnivorous, 5 
are as complicated as in any; but in the Buprestidæ a 
melidæ they are less developed, while they are most rudi ; 
in form and size in the wood-boring weevils and Scolytids 
antennæ and second maxillæ and legs also share in the m 
tion of structure consequent on the burrowing lignivero® T 
of the larvæ. a 
But it is in the so-called hypermetamorphosis of w a 
that of the blister beetle (Epicauta) as well as hoe ‘in the 
been fully described and illustrated by Professor Riley í (pP 
first report of the United States Entomological Commit 
