COLEOPTERA. 509 



manner as the companions of Ulysses watched the sheep of Poly- 

 phemus, so as to escape out of the cave in which they were retained 

 as prisoners. A few days later, and this second larva contracts, and 

 detaches from its body a transparent skin, which discloses a mass, 

 at first soft, which very soon hardens, and becomes of a bright tawny 

 colour; it is called the pseudo-nymph (Fig. 547). It goes through the 

 winter in this state. In the spring comes forth a third larva 

 (Fig. 548), resembling the second. This one does not eat, and moults 

 after a time. It very soon changes into an ordinary pupa (Fig. 549), 

 of a yellowish-white, from which comes forth the adult Sitaris, which 

 lives only a few days, to ensure the propagation of its species, as is 

 observed in the case of the Ephemera. The larvse of the Sitaris had 

 for a long time been remarked clinging on to the hairs of the 



Fig. 5=0. Lampyris noctiluca (male and lc;u.c). 



Anthophoras, but they were always taken for Acari, and they had 

 been described as such. 



The Lampyridce have the elytra weak and soft, like the insects of 

 the preceding tribe. In their perfect state they frequent flowers. 

 The larvae are carnivorous, attacking other insects or worms. It is to 

 this group that the Lampyris noctiluca, or glow-worm, which one sees 

 shining during summer nights on grass and bushes, belongs. It has 

 the power of making this natural torch shine or disappear at will. 



The luminous properties with which these insects are endowed 

 have for their object to reveal their presence to the opposite sex, for 

 the females alone possess these properties. In the same way as 

 sounds or odours exhaling from some insects attract the one towards 

 the other sex, so with the Lampyris a phosphorescent light shows the 

 females to the males. The seat of the phosphorescent substance 

 varies according to the species. It exists generally under the three 

 last rings of the abdomen, and the light is produced by the slow 

 combustion of a peculiar secretion. It has been stated that it is 

 evolved quickly when the animal contracts its muscles, either 



