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sclerit placed anteriorly in the epicranial border; it lies 

 between the ventral articulation of the mandible and the 

 ventral fixation of the tentorium. Pleurostoma lies between 

 the ventral and dorsal articulations of the mandible. Epi- 

 stoma forms the anterior portion of the cranium ; it lies 

 between the dorsal articulations of the mandibles. Epistoma, 

 never differentiated by any of the Carabid-larvæ as labrura 

 and clypeus distinctly separated from the rest of frontale, 

 is divided into nasale (N) and a mandibular sclerit (Mdsk) 

 on each side of the nasale. Between the nasale and the 

 mandibular sclerit a depression is found. Posteriorly, the 

 mandibular sclerit extends to the distal part of the tentorial 

 rib. Nasale is bounded posteriorly by the pharyngeal furrow. 

 Behind this furrow is the somewhat elevated median por- 

 tion of the cranium, accommodating the pharyngeal muscles 

 (1 + 2 + 3). This area is divided into an anterior part 

 from the pharyngeal furrow to an imaginary line between 

 the ocellar areæ (Oa), and a posterior part, the ensiform 

 portion, behind this line. Foremost in the anterior part, 

 and also foremost in the ensiform portion, some small setæ 

 are mostly found. The foremost part is frequently formed 

 as an unpaired, apical portion, the manubrium (1), and two 

 lateral portions, the arms (2). The ensiform part is in some 

 genera (e. g. Oodes) very broad and flatly vaulted ; in others 

 (e. g. Tachypus and Bembidium), narrow and sharpbacked. It 

 inserts itself downwards between the two halves of the cere- 

 bral area. This area (Crb) lies before the hindmost arch of 

 the frontal suture, and covers the superior pharyngeal 

 ganglia. The area of antennal muscles (Am) is found before 

 the anterior arch of the frontal suture; it is apically bounded 

 by the tentorial rib; laterally it joins the cerebral area; its 

 size depends upon the direction of the tentorial rib, the more 

 backwards directed the rib: the more narrow the area; if 

 the rib is wanting the confines of the area cannot by exactly 

 fixed ; it is characterized by a very long and strong seta. — 

 All hitherto mentioned areæ on the surface of the cranium 



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