LUMINOUS INSECTS. 



333 



Besides the different species of the genus Lampyris, all of 

 which, to the number of nearly two hundred, now divided 

 into several distinct genera, are probably more or less 

 luminous, another insect of the beetle tribe, Elater noctilucus, 

 is endowed with the same property, and that in a much higher 

 degree. This insect, which is called the fire-fly, and is an 

 inch long, and about one third of an inch broad, gives out its 

 principal light from two transparent eye-like tubercles placed 

 upon the thorax ; but there is also a luminous patch in the 

 posterior and inferior region of the metathorax, in a some- 

 what triangular and depressed cavity ordinarily concealed by 

 the elytra, but when these are expanded in the act of flying 

 giving out a more considerable but more diffused light than 

 the thoracic reservoirs; in fact the whole body is full of 

 light, which shines out between the abdominal segments 

 when stretched ; and being strongly reflected by the two 

 basal abdominal segments, gives an appearance of the two 

 luminous patches there which De Geer has described, but 

 which do not actually exist. 1 The light emitted by the two 

 thoracic tubercles alone is so considerable, that the smallest 

 print may be read by moving one of these insects along the 

 lines ; and in the West India islands, particularly in St. 

 Domingo, where they are very common, the natives were 

 formerly accustomed to employ these living lamps, which 

 they called Cucuij, instead of candles in performing their 

 evening household occupations. In travelling at night they 

 used to tie one to each great toe ; and in fishing and hunting 

 required no other flambeau. 2 Southey has happily introduced 

 this insect in his i( Madoc" as furnishing the lamp by which 

 Coatel rescued the British hero from the hands of the 

 Mexican priests. 



" She beckon'd and descended, and drew out 

 From underneath her vest a cage, or net 

 It rather might be calTd, so fine the twigs 

 Which knit it, where, confined, two Fire-flies gave 

 Their lustre. By that light did Madoc first 

 Behold the features of his lovely guide." 



Pietro Martire tells us that the Cucuij serve the natives of 

 the Spanish West India Islands not only instead of candles, 



1 Lacordaire, Introd. a VEntom. ii. 141. 



2 Pietro Martire, The Decades of the New World, quoted in Madoc, p. 543. 



