COLEOPTERA 131 



present between pronotum and episternum. Suborder Adephaga; see Table II. 

 AA. Ventral part of the first segment of the abdomen visible for its entire breadth. 

 Suture between pronotum and episternum not present. Suborder Polyphaga; 

 See Table III. 



TABLE II. — ADEPHAGA, THE FAMILIES OF THE SUBORDER 



A. Metasternum with an aritecoxal piece, separated by a well-marked suture reaching 



from one side to the other and extending in a triangular process between the 



hind coxae. Hind coxa? mobile, and of the usual form; habits terrestrial; 



legs fitted for walking. 



B. Antennas inserted on the front above the base of the mandibles. p. 135. 



ClCINDELIDyE 



BB. Antennas arising at the side of the head between the base of the mandibles 

 and the eyes. Beetles with long flat bodies and with the scutellum visible. 



p. 136 CARABID/E 



AA. Metasternum without an antecoxal piece; legs fitted for swimming. 



B. With only two eyes; antennas filiform, p. 138 DytisciDjE 



BB. With four eyes, two above and two below; antennas short and modified in 

 form. p. 139 Gyrinid^e 



TABLE III. — POLYPHAGA, THE SERIES OF FAMILIES OF THE 



SUBORDER 



A. Head not prolonged into a narrow beak, palpi always flexible; two gula sutures 

 at least before and behind (Fig. 212); sutures between the presternum and the 

 episterna and epimera distinct (Fig. 216); the epimera of the prothorax not 

 meeting on the middle line behind the presternum (Fig. 216). 

 B. Abdomen with at least three corneous segments dorsally, and exposed more or 

 less by the short elytra. Hind wings with simple, straight veins; antennas 

 variable, but never lamellate. Series Brachelytra; see Table IV. 

 BB. Abdomen with at most two corneous segments dorsally, usually completely 

 covered by the elytra; hind wings with veins in part connected by recurrent 

 veins. 

 C. Antennas clubbed or not, but if clubbed not lamellate. 



D. Tarsi usually apparently four-jointed, the real fourth segment being 

 reduced in size so as to form an indistinct segment at the base of the 

 last segment, with which it is immovably united (Fig. 218, A); the first 

 three segments of the tarsi dilated and brush-like beneath; the third 

 segment bilobed. Series Phytophaga; see Table VII. 

 DD. Tarsi varying in form and in the number of the segments, but when 

 five-jointed not of the type described under D above, the joint between 

 the fourth and fifth segments being flexible. Series Palpicornia, Poly- 

 formia, and Clavicornia; see Table V. 

 CC. Antennas with a lamellate club. Series Lamellicornia; see Table VI. 

 AA. Head either prolonged into a beak or not; palpi usually short and rigid; 

 gular sutures confluent on the median line (Fig. 213, gs); prosternal sutures 

 wanting; the epimera of the prothorax meeting on the middle line behind the 

 presternum (Fig. 213, em). Series Rhynchophora; see Table VIII. 



TABLE IV. — THE FAMILIES OF THE BRACHELYTRA 



A. Elytra short, leaving the greater part of the abdomen exposed; the suture between 

 the elytra when closed straight; wings present, and when not in use folded 

 beneath the short elytra; the dorsal part of the abdominal segments entirely 

 horny; abdomen flexible, and with seven or eight segments visible below; an- 

 tennas not clubbed at the ends, p 143 Staphylinid/e 



AA. Elytra usually longer, covering the greater part of the abdomen ; when short the 

 wings are wanting or, if present, may or may not be folded under the short 

 elytra when at rest; the dorsal part of the abdominal segments partly mem- 

 branous; antennas usually clubbed at the ends. 

 B. Hind tarsi five-segmented, antennas rarely elbowed, abdomen with six or more 

 ventral segments, anterior coxas conical. 



