COLEOPTERA 473 



HHH. Antennae with the last three segments somewhat larger 

 than the preceding, but not suddenly enlarged, p. 510. 



Derodontid^ 



GG. Posterior coxee not dilated into plates partly protecting the 

 femora. 

 H. Posterior coxae flat, not prominent, covered by the femora in 

 repose. 



I. Tarsi with the fourth joint of normal size. p. 493. Clerid^e 



II. Tarsi with the fourth joint very small, p. 493. Corvnetid^ 

 HH. Posterior coxae conical and prominent . 



I. Anterior coxae with distinct trochantins. p. 493. Melyrid^ 



II. Anterior coxae without trochantins. p. 493. Lymexylid.*; 

 DD. Abdomen with six or more ventral segments. 



E. Anterior cox^ globular. 



F. Tibial spurs well developed, p. 499 Cebrionid^e 



FF. Tibial spurs very delicate and short, p. 499. . . . Plastocerid^ 

 EE. Anterior coxae conical. 



F. Posterior coxae not prominent, flat, covered by the femora in 

 repose. 



G. Tarsi with the fourth joint of normal size. p. 493. . .Clerid^ 

 GG. Tarsi with the fourth joint very small, p. 493. Corynetid^ 

 FF. Posterior coxas more or less conical and prominent at least in- 

 ternally, not covered by the femora in repose. 

 G. Anterior coxae long, with distinct trochantins. 

 H. Abdomen with seven or eight ventral segments. 



I. Middle coxas contiguous ; epipleurae distinct. 



J. Episterna of metathorax not sinuate on inner side, epi- 

 pleurae usually wide at the base. 



K. Head more or less covered; antennae approximate or 

 moderately distant; metathoracic epimera long. p. 491. 



Lampyrid^ 



KK. Head exposed; antennae distant; m.etathoracic 



epimera wide. p. 492 Phengodid^ 



JJ. Episterna of metathorax sinuate on the inner side; 

 epipleurae narrow at the base. p. 492 Cantharid^ 



II. Middle coxae distant; epipleurae wanting, p. 491. Lycid^c 

 HH. Abdomen with only six ventral segments, p. 493.Melyrid^ 



GG. Anterior coxae without trochantins. 



H. Elytra entire; length of body 10 mm. or more. p. 493. . 



Lymexylid^ 



HH. Elytra shorter than the abdomen; length of body less 



than 3 mm. p. 494 Micromaltiiid^ 



AA. Hind tarsi either only three-jointed, or four-jointed but apparently only 

 three- jointed, the third joint being small and concealed in a notch at the end of 

 the second joint. (See also AAA and AAAA.) 

 B. Wings fringed with long hairs. A minute aquatic species from S. Cal. 



and Ariz. {Hydroscapha). p. 485 Hydrophilid^ 



BB. Wings not fringed with hairs. 



C. Tarsi with second segment dilated. 



D. Tarsal claws appendiculate or toothed; first ventral abdominal seg- 

 ment with distinct curved coxal lines, p. 51 1 CocciNELLiDit; 



DD. Tarsal claws simple; first ventral abdominal segment without 



coxal lines, p. 511 Endomychid^ 



CO. I'arsi with second segment not dilated. 



D. Elytra entirely covering the abdomen; ventral abdominal segments 



nearly equal, p. 51 1 Lathridiid^ 



DD. Elytra truncate, the first and fifth abdominal segments longer than 

 the others. 

 E. Maxillae with galea distinct; anterior coxae small, rounded, p. 509. 



M0NOTOMID.E 



EE. Galea wanting, anterior coxae subtransverse. p. 508. Nitidulid^ 



