136 THE CAUSES WHICH PROPAGATE 



Thus^ Dr. Landois finds only eighty-four ridges in either Kmae of 

 the common Dung Beetle {G. stercorarius), each -025 Mm. thick, 

 •36 Mm. broad, but 100 in those of the small vernal sort {G. 

 vernalis), placed at a distance of '02 Mm., and in the green [G. 

 sylvaticu8) 101, -035 Mm. apart. These smaller species, where the 

 limse are finer, have a louder, higher, and clearer note than the first 

 large violet Dung Beetle. In Typhmis vulgaris (Leach) the musical 

 ridge is similar, but the filing very much finer — as fine, indeed, as 

 in the British Ceramhyces. Its leathery creak, therefore, high 

 in pitch, is less intense, resembling the sound produced by 

 drawing the finger over a hair-comb. The lima of this genus 

 is first noticed, I believe, in the " Descent of Man.'^ In some 

 of the warty species of Trox limae are found, as in the Lunar 

 Beetle, according to Westring; and the T. sahnlosus, a little 

 rough coleopteron partial to sandy soil, makes a rattling stridu- 

 lation with its tense elytra, so loud that, it is said, the late Mr. 

 Frederick Smith, on capturing one, induced a gamekeeper to 

 suppose he had found a mouse. 



Passing from the swarthy stercorarious tribes to the bright 

 array of Lamellicornes with larger antennal leaves, that spend the 

 earlier stages of their life under vegetable soil, or in the heart 

 of trees, until, issuing to light, they no longer sap the domain of 

 Flora from beneath, but boom around the leaves inwove in the 

 forest crown, hover at the balmy sap, or rob the flowers of their 

 petals, we again come upon a familiar group — for such are the 

 habits of the nocturnal Atlas Beetles of equatorial America, of 

 the Goliath Beetles of equatorial Africa, and of the cosmo- 

 politan birth of Rose Beetles, Cockchafers, or of strongly man- 

 dibulate Stag Beetles that resound in the cool shadows of 

 fleeting summer. 



The large horned males of the Neo-tropical Dynastida, or 

 Atlas Beetles, all produce a shrill noise by the friction of the 

 abdomen's superior surface on the elytral tips ; and, according 

 to Darwin, in the Rhinoceros Beetle {Orycfes nasicornis, L,), 

 their Palsearctic representative, the limse are seated on the last 

 abdominal segment but one. The females appear to want the 

 musical organs. Spontaneous action of the nervous system to 

 produce fear in the guise of spite or anger is well seen in one 

 of the tropic Stag Beetle kind. " ChiasogiuUhus grantii, of 



