PHOSPHORIC INSECTS. 147 



Latreille has been most attentively studied. This 

 insect, of a dark brown colour, attains about one 

 inch and a half in length. On its back are ob- 

 served two smooth yellow spots. It is extremely 

 common in the Antilles and the whole of South 

 America, and emits a much more vivid light than 

 the LampyridfB. Besides the two yellow dorsal 

 spots, which are very brilliant at night, there 

 exist two others, hidden under the wing-cases or 

 elytra, the light of which is only visible when the 

 insect flies ; it then shows four luminous points of 

 great brilliancy. Moreover, the whole body of 

 the insect appears glittering with light, which 

 shines through the intervals existing between 

 each segment or ring of the abdomen, and which 

 is easily perceived when these segments are gently 

 pulled asunder. The light which is emitted by 

 the two points upon the thorax alone, is suffi- 

 ciently strong to allow us to read by its aid the 

 smallest print. 



Under the common name of Fire-flies a great 

 number of these exotic Elaters are indistinctly 

 grouped. Most of them are smaller than Elater 

 noctilucus. Closely allied to this is E. ignitus. 

 But, besides these two species, Illiger has described 

 ten others under the generic name of Pyr jphorus ; 

 and Kirby and Spence state that seventy distinct 

 species of these luminous insects are spread about 

 the hot climates, from Chili to the south of the 



