134 THE CAUSES WHICH PROPAGATE 



of love and rivalry, or the music is maternal, since they stridu- 

 late when aggregating to feed, when chasing the female, or 

 when rolling the balls which contain their ova. But on 

 Palsearctic areas the intelligence of the large stercorarious 

 coleoptera is not in direct ratio to the stridulation, as the 

 Scarabffiidse appear certainly less musical but most gifted. Thus 

 • while the female of our common Dung Beetles ( Geotrupes) merely 

 grubs a vertical hole and deposits her ova in some dung she 

 drags to the bottom, the Sacred Beetles belonging to the 

 genera, Ateuchus (Fab.), and their American allies, Gymnopleiirus, 

 Illig., roll a mystic ball in company, pushing it backwards, 

 and then inter it, as the ancients imagined, with solemn rite, to 

 await a recreation of their kind. Our indigenous Lunar Beetle, 

 Copris Imiaris, also works in couples, as may be ascertained 

 by examining its holes. 



The stercorarious species of Copris, Onthophagus,Q.ndiAteuchus, 

 have the abdominal rings so anchylosed as to preclude segmental 

 motion; yet the Lunar Beetle is stated to produce a considerable 

 noise by the friction of the abdomen against the hinder margin 

 of the elytra; and Westring and Darwin go so far as to find 

 minute limaj on raised oblique ridges running along the sutural 

 margins from the elytral tip to a quarter their length, which 

 appear to rub on the sides of a posteriorly converging depression 

 at the centre of the last dorsal arc but one. Other Coprini 

 have the files transposed to the dorsal surface of the abdomen. 

 In the genera of another group the limse are on the hind 

 coxae. Darwin, quoting M. P. de la Brulerie, says : " The male 

 Ateuchus stridulates to encourage the female in rolling her ball, 

 and from distress when she is removed ; " and in the sexes of 

 a Sacred Beetle, common in foul ravines behind Castellamare, I 

 found a prominent, though not well defined, linear lima on the 

 inferior surface of the hind coxae near the femoral articulation, 

 which, during the rotatory action of ball-rolling, naturally 

 pressed against the inferior metathoracic surface, producing 

 thereby a just distinguishable sand-papery note. 



The cow, camel, ass, and even the marsupial quadrupeds of 

 Australia, have all allotted satellite beetles to follow them on 

 their pastures, although these are quite independent as regards 

 their law of distribution. Coeval \nt\x the cow and third period 



