BEETLES. 367 



mandibles. The images of one portion of this family are mostly vegetable feeders, 

 often living upon leaves ; those of another portion feed upon the excrement of higher 

 animals ; a few eat fruit, flowers, or honey, even, exceptionally, entering bee-hives to 

 steal honey ; certain species also lick the sap from wounded places on trees ; and a 

 very few (e. ff., Trox) feed upon decaying animal matter. In their sexual relations, 

 some species of lamellicoi'ns have strange habits. JElaphocera bedeaui, a common 

 species in the sand dunes of the Bay of Cadiz, copulates only during storms ; at other 

 times the beetles remain concealed in the sand. In Bolboceras gallicus, a French 

 species, the two sexes inhabit neighboring burrows a foot deep in the ground, and the 

 male digs a passage out from his own burrow to that of the female. The males of 

 Polyphylla variolosa, from the eastern United States, have been seen vigorously 

 scratching the ground above places where females were about to emerge from their 

 pupse, presumably guided to them by the sense of smell, a sense which has reached a 

 high degree of development in the lamellicorns. The aid which certain male dung- 

 beetles give the females in their maternal duties will be more fully noticed further on. 

 The males of lamellicorns are usually much larger than the females, and are often 

 easily distinguishable from the latter by horns upon the prothorax or head, by better- 

 developed antennae, or by modifications of the legs. 



The larvae of the Scarabseidas are rather robust, white grubs. Their anal end is 

 curved around under their body so that they cannot walk on a flat surface, but are 

 only able to use their six well-developed legs in locomotion when surrounded by the 

 substances in which they live. The head is corneous and resistant, with four-jointed 

 antennas and without ocelli. The rest of the larva is covered with a somewhat tough 

 skin, and widens posteriorly so that the apical half of the abdomen is broader than its 

 base. All lamellicorn larvae live concealed, some in the ground, feeding upon roots, 

 others in decaying wood, in excrement, or in other substances which they devour. 

 The coprophagous species undergo their metamorphoses rapidly, but the other lamelli- 

 corns often require two or three years to pass from the egg to the imago. Several 

 nematode worms inhabit the capacious digestive tract of certain lamellicorn larvae ; 

 but, besides these, the larval stage of Echinorhynchus gigas, an acanthocephalous 

 worm which lives as adult in the intestinal canal of swine, has been found in the grubs 

 of the European May-beetle {Melolontha vulgaris). The swine eat the May-beetle 

 grubs, thus infecting themselves with worms, and the dung of the swine furnishes the 

 May-beetle grubs the eggs of the worm — a curious interrelationship between hog, 

 worm, and insect. The larvae of certain lamellicorns are subject also to fungus para- 

 sitism by species of Torruhia, of which the fructification stems grow out from the 

 grubs killed by the fungus, often to the height of several inches, giving rise to stories 

 of grubs changing into plants. 



Dr. Le Conte has divided the Scarabaeidffi into three sub-families, according to the 

 position of the abdominal stigmata. In the lowest sub-family, the Scarabaeidae pleu- 

 rosticti, the abdominal stigmata (except the anterior ones) are " situated in the dorsal 

 portion of the ventral segments, forming rows which diverge strongly ; " the last pair 

 of stigmata is visible behind the elytra. 



Osmoderma has the thorax considerably narrower than the elytra and usually 

 rounded at the sides; the posterior coxae are contiguous, and the outer lobe of the 

 maxillae is corneous. 0. scabra is about 0.9 of an inch long, with a roughened but 

 shining coppery or brownish-black surface. Its larva lives in decaying rosaceous 

 wood, and pupates in an oval cocoon made by cementing together fragments of the 



