206 NATUEAL HISTORY OF 



holes (lug in the earth or in the decomposed trunks 

 of trees, or they are observed running along the 

 pathways in the woods. On the approach of night 

 they issue from their retreats, and fly around the 

 trees at a considerable height above the ground, 

 producing at the same time a loud noise. It is then 

 that they seem to procure their food ; and they are 

 sometimes found in the morning under the leaves 

 or clinging to the branches of trees. Although their 

 flight is dull, it is rather rapid, and can be prolonged 

 for a considerable time. They all produce a shrill 

 noise by rubbing the elytra against the abdomen. 

 The females are in general more common than the 

 males, and are almost always without horns. Among 

 the few exceptions to this rule may be mentioned 

 S. Pan, the most common species in Brazil, the fe- 

 male of which has a horn of some size on the head, 

 and an excavation on the thorax. The latter sex is 

 common, while the male is rare. 



The first species selected to illustrate this genus 

 is the largest, and in some respects one of the most 

 remarkable that it contains. It is named the Her- 

 cules Beetle : — 



