20 



The insect whose song is most frequently heard in Guiana is the C't- 

 caJa clarisona, the Aria-aria of the Indians, and Razor-grinder of the 

 Colonists : in the cool shade of the forests it may be heard at almost 

 every hour of the day } but in Georgetown its song commences as 

 the sun disappears below the horizon. At Georgetown this Cicada 

 was never heard in 1804, when Dr. Hancock first visited the place j 

 but it is now very common, probably in consequence of the shelter 

 afforded by the growth of many trees and slirubs in the gardens which 

 have since been formed there. The sound emitted by it is " along, 

 continuous, shrill tone, which might be compared almost to that of a 

 clarionet, and is little interrupted, e.\cept occasionally by some vibrat- 

 ing undulations." 



