600 The Influence of Magnetism on the October, 
shine uniformly over their whole extent, but that sometimes 
one spot and sometimes another glows more strongly. If 
such a specimen is examined under the microscope we per- 
ceive, on a dark back-ground, bright luminous rings, which 
are not, however, uniformly brilliant, but display certain 
more intense points which flash up and again disappear, or 
continue to shine on faintly for a time, reappearing after- 
wards in full splendour. These changes take place without 
any regular succession. 
Signor Emery concludes that the luminous combustion 
takes place on the surface of the parenchymal cells, but not 
in their substance. These cells probably secrete the lumin- 
iferous matter which is taken up by the terminal tracheal 
cells, and is burnt by means of the oxygen encountered in 
the tracheal capillaries. Emery does not consider that the 
emission of light is a sexual attraction for the females, which 
are rarer. He suspedts that it rather serves to deter insect- 
ivorous noCturnal animals. 
X. THE INFLUENCE OF MAGNETISM ON 
THE DEVELOPMENT OF THE EMBRYO. 
S ^ROF. CARLO MAGGIORANI has recently read an 
account of some experiments on this subject before 
the Academy dei Lincei. 
During the process of artificial incubation the author ex- 
posed a number of eggs to the influence of powerful magnets. 
A similar set of eggs, being hatched in the same manner, 
but kept away from all magnetic aCtion, served as a check. 
Cases of arrested development were four times more nume- 
rous in the first group than in the second. Analogous faCts 
had been previously published in the “ Natura” (Florence, 
1878). Microscopic examination showed that the sterilisa- 
tion of these germs was probably due to an intense vascu- 
larisation of the yolk-sac. 
After the birth of the chickens this increased mortality 
continued, deaths being three times more numerous in the 
magnetised group. All the counter-test chickens reached 
