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antennal muscles; Ask, aiitennal sclerit; Crb, cerebral area-. Col, Collum; 

 Crvf, cervical furrow; Df, the distal dorsal furrow: E, epicranium: Es, 

 epicranial suture; Est, epistoma; F, frontale; FF, the final area of 

 frontale; Fs, frontal suture; Mdsk, mandibular sclerit; N, nasale; Nt, 

 nasal tubercle; Oa, ocellar area; Of, ocellar furrow; Pf, proximal dorsal 

 furrow; Phf, furrow in the pharyngeal line; Plst, pleurostoma,' T, ten- 

 torium ; Tc, condyle-shaped apex of tentorium ; V, vertex. 



inferior side of prothorax. The two halves of the epicranium 

 noeet in the gular suture (t — s). To each half of the epi- 

 cranium belongs a fourjointed antenna and a mandible. The 

 basal part of the antenna is surrounded by a ringshaped 

 antennal sclerit (Ask). The mandibles ventral condyle fits 

 into a fossa (Mdf) in pleurostoma; its dorsal fossa articu- 

 lates with a condyle (Tc) at the apex of tentorium. The 

 tentorium (T) is a chitinous rod in each half of the cra- 

 nium ; it extends downwards through the half of the cranium 

 and is fixed (t) at the apical end of the gular suture. The 

 dorsal part of tentorium is in most genera grown together 

 with frontale, and a chitinous rib is then seen on the surface, 

 the tentorial rib (T). This rib is running inwards and may 

 be directed more (e. g. Calathus) or less (e. g. Bembidium) 

 backwards; it is only wanting in some few genera (e. g. 

 Blethisa, Elaphrus and Broscus). In the interior of the 

 cranium, tentorium detaches, at any rate, one branch, that 

 meets the branch from the opposite side, and forms with 

 it a bow below oesophagus. The mouth is large; one man- 

 dible in each buccal commissure. The skin of the commis- 

 sure is turned bag-like inwards, around the bases of the 

 mandibles, when these bite together, but are drawn hill-like 

 out when they are thrown back. On the under side of the 

 cranium, the broad anterior border of the pharynx is attached 

 along the pharyngeal line between the dorsal articulations 

 of the mandibles. In, or close to this line, one or a few 

 cross-furrows are found on the surface of the head, the 

 pharyngeal furrow (Phf). — The frame of the mouth is 

 constituated by hypostoma (Hst), pleurostoma (Plst) and 

 epistoma (Est). Hypostoma is a rather broad, triangular 



