1916] Reflex " Bleeding" of Epilachna 215 



Cuenot (1896b) summarizes his investigations by saying that 

 Timarcha, Galeruca, Megalopiis, coccinelHds and meloids among 

 the Coleoptera, and Eugaster and Ephippiger among the 

 Orthoptera possess the phenomenon of reflex bleeding. When 

 disturbed they feign death and eject drops of blood from the 

 mouth, femoro-tibial articulations and from the articulations of 

 the first pair of wings. In all these species the blood comprises 

 toxic, caustic or repulsive products. It is an important means 

 of defense against lizards and batrachians. 



Lutz (1895) asserts that in the Coccinellidse, blood coming 

 from the distal end of the femur issues through a slit on either 

 side of the articular membrane which surrounds the chitinous 

 rods (vSelane) to which the extensors of the tibia are attached. 

 The blood exudes by a forced contraction of the abdomen and 

 by the flexors of the tibia, and it is a voluntary act. It is a 

 means of defense because the blood is actually quite repulsive 

 to insectivorous animals. In Timarcha, Meloe, etc., as in the 

 coccinelHds, the device of ejecting blood from the femoro-tibial 

 articulations is to permit the blood to escape from the legs rather 

 than through the mouth. 



Packard (1895) states that many beetles, such as the oil 

 beetles Meloe, Cantharis and Lytta, emit drops of blood from 

 the femoro-tibial articulations as a means of defense. The 

 cantharadine produced by these insects is formed in the blood 

 and in the genital organs. It is so extremely caustic that 

 scavenger insects feeding upon the dead bodies of these beetles 

 leave untouched the parts containing cantharadine. Coccin- 

 elHds are also protected by a yellow mucilaginous and disagree- 

 able fluid which is emitted from the sides of the thorax. 



Of those who advocate the view that the discharged liquid 

 is blood, Leydig is the only one who has studied sections passing 

 through the femoro-tibial articulations. And even he admits 

 that his view is not well founded, because he failed to find any 

 openings at these articulations. Lutz has certainly mistaken 

 some other structure for sHts. Perhaps he has seen the olfactory 

 pores which often He where his supposed sHts were observed. 



The following authors beHeve that the discharged Hquid is 

 a glandular secretion. 



Magretti (1881) imagines that the discharged liquid from 

 Meloe is secreted by gland cells in the legs. 



