An interesting exception occurs in the Malacodermidae, where this coadaptation is wanting, or is imperfect; they are frequently considered to be the most primitive of existing beetles.
In a series of memoirs in various German periodicals during the last five or six years (see especially Deutsche ent. Zeit. 1893 and 1894, also subsequent years of Arch. Naturges.). It should be noticed that in the course of his studies Verhoeff has modified some of his earlier views.
We consider this term inferior to Tetramera for nomenclatorial purposes.
Danske Selsk. Skr. (6), viii. No. 1, 1895.
Horae Soc. ent. Ross. xiv. 1879, p. 15.