CARIBICI. 179 



under which they live ; but it is probable that they 

 frequently come to the surface to breathe, like the 

 Dyticidce and others of our fresh- water Beetles. 



There is, however, besides these, the larva of 

 some two -winged fly, which is marine. I have 

 repeatedly taken it on our southern shores, quite 

 out of the influence of fresh water. It was pro- 

 bably this larva (which is white, and half-an-inch 

 in length) that Dr. Johnston described as an 

 Annelid, by the name of Campontia eruciformis 

 (" Zool. Journ." iii. 325). That my specimens are 

 those of a Dipterous larva, I have the high autho- 

 rity of Mr. Francis Walker, who examined one. 



INSECTA. 



Three pairs of jointed legs; one pair of antennae ; 

 body divided into head, thorax, and abdomen ; 

 breathing performed by two parallel air-pipes, 

 opening by numerous spiracles on each side ; un- 

 dergoing complex metamorphosis. 



Order COLEOPTERA. 



Two pairs of wings, the fore pair having the 

 form and office of stiff leathery sheaths for the 

 second; two pairs of jaws. 



TEIBE I. CAEABICI. 



Lower jaws (maxillce) simply hooked at the tip, 

 not jointed at the base, two feelers (palpi] to each 

 maxilla; antennae thread-like; wing-sheaths cover- 

 ing the abdomen, which is covered above with a 

 thin skin. 



N2 



