Crampton: Sclerites of the Head 69 certain Diptera, the epipharynx may become long and stylet-like, forming with the labrum, the so-called labrum-epipharynx. In the orthopteroid insects the epipharyngeal region usually does not project to any great extent, and in such cases consists of the membranous inner lining of t Ill'labrum and clypeus (i. e., the" roof of the mouth ") bearing hairs ami taste organs frequently arranged about a Y-shaped thickening ncar the median region. In certain of these orthopteroid insects, the labrum may be partially divided into an anterior and posterior area ealkll the antelabrum and postlabrum, by an incomplete transverse suture or hy cmarginations of the sides of the labrum. As was previously mentioned, Riley, 1904, considers that the clypeus, together with the labrum, frons, etc., arose from the first or protoC'l'rdlral segment of the embryo. The clypeus, labeled" cl" in all Fi~'1.m's, extends from the labrum (or the labral suture) posteriorly to the dypeal suture, which, however, may be obsolete in some insects. When thl' clypeal suture has disappeared, the posterior limits of the c1ypeus arc demarked by a line drawn across from the base of one mandibk to the base of the other mandible, since the clypeal suture, when prt'sent, corresponds in general to such a line connecting the bases of the mandibles, which are therefore the chief" landmarks" delimiting the postl'rior extent of the clypeus. This fact is of considerable importance, since the area usually called the clypeus in the Psocidre,etc., lies behind the line connecting the bases of the mandibles, and is therefore in all probability an anterior portion of the frontal region. The entire clypeal region may be but slightly chitinized and pigmented, giving the appearance of a membranous area, as is the case with the region labeled" cl" in Fig. 79 of a larval Lepidopteron, or in Fig. 39, of the termite },f astotermes. In other instances, as is the case in the Neuroptcron Raphidia, shown in Fig. 33, and less clearly in the earwig shown in Fig. 36, the posterior region II pc" of the c1ypeus may be strongly chitinized and pigmented, while the anterior region "ac" is not strongly chitinized and pigmented (i. e., has a membranous appearance) thus differentiating the entire clypeal region into an antecl ypeus "ac" and a postclypeus, "pc." Occasionally, the c1ypeus is divided into an antec1ypeus and a postclypeus by a transc1ypeal suture extending transversely across it. In the larva of the Neuropteron Sialis, shown in Fig. 40, the clypeal region II cl" is retained in a condition more nearly approximating the primitive, or original one. If one will compare this larva with those of the Neuroptera Raphidia and Corydalis, shown in Figs. 41 and 42, one may sec that while the clypeal suture extends clear across from the base of one mandible to the base of the other in the larval Sialis shown in Fig. .to, (i. e., the line of the posterior border of the area II cl" extending from the base of one antenna to the other) this same clypeal suture i...

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Eucyrtopogon cornantis iiew speciesDorsuni of thorax with conspicuous white mane anteriorly; arista ahout two-thirds as long as third antenna1 segment.Length [11][12] nun. h f a l e . Face inoderately convex, thickly covered wit11 white pollen, lnystax chiefly black, but the silvery white hairs nunierous so that it appears chiefly white except in the luiddle and below; front opaque black, the orbits thinly silvery pollinose; pile luteous, on the ocellar swelling black, tipped with white. Occiput n-ith white pile, the occipital ciliae luteous, the pile in their vicinity inore or less so; cheeks with black pile tipped with n-hite Antennae black, with a whitish bloon~, illore yellowish on the first two segments, the pile pallidly luteous, one or two long hairs below the second segment. brownish; third segment narrow, gradually tapering, the immediate base swollen; arista slender, its basal segment thicker than the median, short, the apical segment spinose.Thorax with the ground color shining black; a broad, geminate, complete ~nediaii longitudinal stripe, blacliish, the median whitish line not al~vays distinct; on either side and above the roots of the wing a whitish vittae; elselvhei-e on the dorsuiu and on the pleurae more or less thickly covered with olivaceous yellow or golden bron-nish pollen. On the middle line a conspicuous white inane on the anterior half, bordered laterally by long black hairs; long white hairs just before the scutellum, elsewhere on the dorsum, 11lrcIc. the bristles bro~rmish, tipped ~v i t h white; on thc pleura white, on the epimerun luteous yellow, the hairs below ~vhite. Scutelluln conrex, thinly, velvety hron-n-is11 yellow, nrith abundant fine ~v l~i t e pile ; 111-istles long, slender, black, hecoii~ing yello\v, the ends silvery white.Legs black, the tibiae chestnut, pile chiefly yellow 011 the base of the hairs, the ends silvery white, so that it appears nlixed yellowish and IT-hire; bristles piceous or piceous reddish. Anterior tibiae internally, the posterior ones intero-posteriorly and their tarsal cushions bright brownish red.Wings chiefly hyaline, the apical portion greyish villous; crossveins ;.nd bifurcation of third vein and furcation of foul-th and fifth veins clouded \~-ith brown; costa wit11 double rom7 of abundant curved spinulose hairs.Abdomen shining greenish black; on the disc xvith short yellow, laterally wit11 rather abundant, fine white pile, the bases oE the hairs rather tawn?-, so that the pile appears intermixed; on the basal two segments mostly white ; on the sixth ventral seginent dense, sharply lin~ited apically, reddish or tawny basally, the ends of the hairs white, but soine black hairs intermixed. 011 the sides of the first to sixth segments apically a sn~all, sub-oval greyish sericev~is spot.