472 AN INTRODUCTION TO ENTOMOLOGY 



K. Anterior coxae with a distinct trochantin. p. 505. 



DASCILLID.E 



KK. Anterior coxae without trochantin. 



L. Lacinia of the maxillae armed with a terminal 



hook. p. 505 EUCINETID^ 



LL. Lacinia not armed with a terminal hook. p. 505. 



Helodid^ 



HH. Posterior coxae flat; not grooved for the reception of the 

 femora. 



I. Tarsi more or less dilated, first segment not short. 



J. Antennae eleven-jointed, terminated by a three-jointed 



club. p. 508 NlTIDULID^ 



JJ. Antennae ten-jointed, club two-jointed, p. 508 



Rhizophagid^ 



II. Tarsi slender, first segment short, p. 508. .Ostomid^e 



GG. Anterior coxae globular. 



H. Presternum with a process which extends backward into a 

 groove in the mesosternum. 



I. The first two abdominal segments grown together on the 

 ventral side. p. 502 Buprestid^ 



II. Ventral segments free. 



J. Prothorax loosely joined to the mesothorax; front 

 coxal cavities entirely in the prosternum. 

 K. Posterior coxae laminate ; trochanters small. 



L. Antennae somewhat distant from the eyes, their in- 

 sertion narrowing the front, p. 502 Eucnemid^ 



LL, Antennas inserted under the margin of the front. 

 M. Antennae arising near the eyes. p. 499.Elaterid^ 

 MM. Antennae arising at a distance in front of the 



eyes (Perothops). p. 502 Eucnemid^ 



KK. Posterior coxas not laminate; trochanters of middle 



and posterior legs very long. p. 499. . . .Cerophytid^ 



JJ. Prothorax firmly joined to the mesothorax; front 



coxal cavities closed behind by the mesosternum. p. 502 



Throscid^ 



HH. Prosternum without a process received by the mesoster- 

 num, although it may be prolonged so as to meet the meso- 

 sternum. 



I. Posterior coxae contiguous, p. 511 Phalacrid^ 



II. Posterior coxae separated. 



J. Body depressed; middle coxal cavities not closed ex- 

 ternally by a meeting of the mesosternum and meta- 



sternum. p. 509 Cucujid^e 



JJ. Body more or less convex; middle coxal cavities en- 

 tirely surrounded by the sterna. 

 K. Prosternum not prolonged behind, p. 510. . . 



Mycetophagid^ 



KK. Prosternum prolonged, meeting the mesosternum. 

 L, Anterior coxal cavities open behind, p. 510.... 



Cryptophagid^ 



LL. Anterior coxal cavities closed behind, p. 509 



Erotylid^ 



FF. Anterior coxas conical, and projecting prominently from the 

 coxal cavity. 

 G. Posterior coxae dilated into plates partly protecting the femora, 

 at least at their bases. 



H. Antennae serrate or flabellate. p. 499 Rhipicerid^e 



HH. Antennae with the last three segments forming a large club. 



I. Tarsi with second and third segments lobed beneath, 

 p. 510 Byturid^ 



II. Tarsi simple, p. 506 Dermestid^ 



