4g6 DESCRIPTION OF THE MUSEUM. 



which they called tettigometrce , and even the per- 

 fect insect. The c. orni (n° 25) makes an incision 

 in the flowering ash, whence exudes the honied 

 and purgative juice named manna. The genus 

 cicadella is allied to the preceding. 



The bugs are divided into two great families, 

 the terrestrial or geocorisce, and the aquatic or 

 hydrocorisce. They are generally carnivorous 

 and of an highly unpleasant smell. The rediwii, 

 Fabr., belonging to the family of the geocorisoe, 

 have a sharp snout and a formidable sting. The 

 larva of the cimex per sonatas, Lin. (n° 5), inha- 

 bits our houses ; it resembles a spider covered 

 with dust, and feeds upon the common domestic 

 bug. 



To the family of the hydrocorisce belong the 

 genera hydrometra, nepa or water scorpion, 

 notonecta, naucoris, and corixa. The nepa 

 maxima (n° i) is a very large insect, from South 

 America. 



Those hemiptera in which the body of the fe* 

 males increases very considerably towards the 

 season for laying, when they acquire the form 

 of a gall nut, are called gall-insects. To this fa- 

 mily belongs the cochineal insect [coccus cacti) , 

 which yields so beautiful a colour, a native of 

 South America, imported from Mexico with the 

 cactus opuntia. The order of the hemiptera is 



