. The fossil insects of North America, with notes on some European species [microform]. Insects, Fossil; Insects; Insectes fossiles; Insectes. 1 }' â (. 4 ill: i' I 1 1^ 60 PALAEOBLATTARIAE. Palaeozoic cockroaches; in which the fore wihgs are diaphanous, generally reticulated and nearly symmetrical on either side of a longitudinal middle line; the externomedian vein is completely developed and divides in the outer half of the wing, its branches gener- ally occupying the apical margin. The internoiaedian area is broad at its base (beyond the anal area), rapidly tapers apically and is filled wit
. The fossil insects of North America, with notes on some European species [microform]. Insects, Fossil; Insects; Insectes fossiles; Insectes. 1 }' â (. 4 ill: i' I 1 1^ 60 PALAEOBLATTARIAE. Palaeozoic cockroaches; in which the fore wihgs are diaphanous, generally reticulated and nearly symmetrical on either side of a longitudinal middle line; the externomedian vein is completely developed and divides in the outer half of the wing, its branches gener- ally occupying the apical margin. The internoiaedian area is broad at its base (beyond the anal area), rapidly tapers apically and is filled with oblique, mostly parallel veins, having nearly the same direction as the anal veins, which, like them, strike the inner margin. Their bodies appear to have been flat, but slenderer than usual in cockroaches of the present day, the pronotal shield depressed, more or less elliptical, but sometimes longer than broad, the head partly concealed by it as in living types. They were of large size; but while the average was considerably above that of existing cockroaches' none were much larger than some S. American species of Blabera. Germar was the fii'st to note the diaphaneity of the fore wings,'' and Goldenberg the presence of the externomedian vein,^ and the course of the anal branches.* Ml'LACKlDAE. In this group the mediastinal vein of the tegmina Avith its branches consists of a number of veins, simple or forked close to their origin, spreading in a fan shape and appearing to arise from a single point or near a single point close to the base of the wing; or in other words, the branches originate from the main vein close to its base and to each other, the outermost being much'longer than the innermost, often double as long as it, and either straight or uniformly ai .late; the area of the vein is thus triangular and more or less than half as long as the wing. The character of the vein therefore much more nearly resembles that of the anal vein than of the others. The group is con
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectinsects, bookyear1890
