30 Dr. John Davy's Observations on 



a sprinkling of a matter on their surface of a lighter hue. One 

 broken up, mixed with water, under the microscope exhibited 

 minute granules, as of lithate of ammonia, particles of an irregular 

 form, as of earthy matter, a few forms as of infusoria, and fibres, 

 &c., as of vegetable matter. The pellets, digested in dilute nitric 

 acid, separated into smaller ones, seeming to show casts of the 

 intestines. The solution (the greater portion of the excrement 

 remaining undissolved), evaporated and heated, afforded proof of 

 the presence of lithic acid. 



After having been killed by the vapor of camphor, an opaque 

 filament was seen adhering to its anal extremity. This, digested 

 in water and slightly agitated, under the microscope exhibited 

 granules like those of lithate of ammonia, with a filamentous sub- 

 stance, probably mucus. The granules, about ^ q\q q of^ an i'lch 

 in diameter, were immediately dissolved in dilute nitric acid, and 

 on the application of heat the purple hue was produced denoting 

 lithic acid. 



5Q. A beetle (Geotriipes stercorarius), in confinement, voided 

 some excrement of a soft consistence, and nearly white, which was 

 found to consist principally of lithate of ammonia. Killed by 

 immersion in water, and opened, white vessels were seen on the 

 intestine containing an opaque matter, which, tested by nitric acid 

 and heat, proved to be lithic acid or lithate of ammonia. 



57. A beetle (B/rt^w mort'isnga), in confinement, voided some ex- 

 crement in the form of pellets of a dark grey colour, partially 

 covered with a crust of lighter hue. Broken up and mixed with 

 water, under the microscope the prevailing color was light green- 

 ish, from vegetable matter in fragments, amongst which were in- 

 terspersed many granules, as of lithate of ammonia. Digested 

 for a short time in dilute nitric acid, and the solution evaporated 

 and heated with care, proof, in the color produced, was obtained 

 of the presence of lithic acid. 



38. A female Telejihorus pilosus voided in confinement a little 

 excrement, which was found to consist principally of granular 

 lithate of ammonia. 



59. A male Telephorus Melanurus(J) taken in company with 

 the preceding, and in the act of coitus, died in confinement 

 without voiding any excrement. The anal extremity detached, 

 acted on by nitric acid and heat, afforded a trace of lithic acid. 



The trials on the four following insects were made about twelve 

 months after their death, kept, put by in a drawer, without any 

 care ; they were some of those on which experiments had been 

 tried to show the effects of different agents on insects, as described 



