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importance with regard to systematic arrangement, since,as the author rightly observes, “ it affords at least secon-dary Family characters.”
The author distinguishes three forms: (1) Orthotropous wings (alse ortko-tropae) without any slanted fold, and without flexure (brack); Molorchus,Atradocerus, Lyons (he also adduces Carabus, relying upon the circumstancethat in Carabus granulattis wings of moderate length are found under theelytra; but these wings are not perfectly formed, and consequently cannot betaken into account; when, in an unusual way they are fully developed theyassume, in that species, the third form. (2) Anatropous wings (al® ana-tropse), doubled back, without slanted folding; ( Trichopteryx , Scaphidium,Catops, and those that were examined of various Curculionid ®). (3) Pla-giotropo'us wings (al® plagiotrop®) bent back, and at the same timefolded, so that the anterior margin of the wing in the closed position formsa more or less acute angle, whilst in the anatropous wings the anterior marginis doubled back upon itself. This third form is by far the most frequent, andexhibits many modifications, which are described in a very succinct manner.
Heer (Entom. Zeit. p. 51, T. ii) has also submitted toexamination the articulation of the abdomen of the Cole-optera.
He correctly remarks that in the larva there are generally nine abdominalrings present, that nine is also in the perfect beetle, to be assumed as thenormal number for the segments of the abdomen, and that this number isonly apparently diminished in consequence of some of the segments, either atthe base or at the apex, being retracted or concealed. This is morethe ease on the abdominal than on the dorsal face, whence the abdominalsegments depart more from the normal number than those of the back.Besides the mere number of the segments of the back and abdomen, theirmutual relations also are to be taken into consideration. In this respect theauthor distinguishes four cases :
(1) Each abdominal segment corresponds with one dorsal segment, but thefirst of these is frequently not continued on the abdominal surface. ( Bra-chelytra, Silphidai, true Lamellicornia.)
(2) The first abdominal segments are opposed to single dorsal segments;—the first abdominal segments are continued immediately into single dorsalsegments, but to the last abdominal segment are opposed two or threedorsal segments. ( Carabida, Lucauida , Materidce, Byrrhidce .)
(3) To the first abdominal segments are opposed from two to three dorsalsegments, but to the rest of them only single dorsal segments; the last,however, normally is retracted within the penultimate one. This conditionis frequent, as for instance in the Longicornes .