FIELD BOOK OF INSECTS. 



Ceruchus piceus: black or dark reddish-brown; male's 

 mandibles as long as the head, with a large median tooth; 

 female's mandibles about half as long as the head, with 

 three or four blunt teeth on inner side; elytral grooves 

 shallow. 



Passalus cornutus (Plate LXXIX) can make a creaking 

 or a hissing noise by rubbing the elytra. The third pair 

 of larval legs are aborted but in some species, at least, 

 are used to make a noise by scratching the roughened 

 middle legs. Some authors put this genus in a separate 

 family, PASSALID^:. 



Nicagus obscums (Plate LXXIX) occurs under drift 

 in damp, sandy places. 



This large family (nearly 20,000 species and "increasing 

 by the discovery of about 300 new species every year") 

 contains such forms as the May Beetles (June Bugs), the 

 "shard-borne beetle with his drowsy hum" of Shakespeare, 

 and the Sacred Scarab of Egypt. The larvas are usually 

 yellowish-white, with a brown, chitinized head bearing 

 prominent mandibles; they are wrinkled, fat (especially 

 at the hind end) "grubs" which live in excrement, in 

 decaying wood, or in the ground, and normally lie on their 

 side with the hind end almost, or quite, touching the legs. 

 Several methods of classifying the members of this family 

 are in use, of which the following is about as convenient 

 as any. 



Coprinas 



Most of these differ from the rest of Lamellicorns by 

 living in dung and other animal matter. The abdominal 

 spiracles (breathing holes) are placed in a line on the 

 membrane connecting the dorsal and ventral plates and 

 are covered by the elytra when the wings are closed ; upper 

 surface of the head usually much dilated on the front and 

 sides. All except the Acanthocerini and Trogini have six 

 visible, ventral, abdominal segments. 



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