412 Correspondence of J. Nickles. 
animal. The life of the females is almost vegetative; with an out- 
ward form so undeveloped as to quile resemble a larva, she fastens 
herself to the leaf or bark, and, drawing the juices therefrom, develops 
her ovaries, successive litters of eggs being formed ; and, as the condi- 
impregnate the females. The means I shall recommend for a removal 
of this pest, will be based upon a consideration of the intimate econ- 
omy of the animal. 
Correspondence of M. Jerome Nickles, dated Paris, February 27, 1854. 
At one of its late sessions, the Academy of Sciences awarded the 
annual prizes to authors of works on different subjects proposed Dj 
and also * encouragements” to those who have distinguished themselves 
by researches in their own proper domain. As the list of prizes is 
long, we will only mention those of more special interest. 
1. ‘The Academy awarded the prize in Mechanics to Felix Fro 
pe 
4 
moderateur,” brought forward by him in 1836 and 1837, the use of 
which has now become general; ( i i 
report upon them was made by the distinguished engineer and mecha- 
nician, M. Combes, at this moment President of the Academy of Sciences. 
the application of steam to navigation and to naval force. Sine this 
epoch, until 1848, great improvements have taken place, but they were 
not first put in practice in France; they were brought out in America 
and England. But now, by the construction and success of the “ Ne: 
poleon,” a vessel of the line with sails and steam, the end of the prize 
has been completely attained. The Academy has consequently assigned 
the prize (1) to M. Dupuy de Léme, officer of the naval Engineer COFPS, 
for devising and constructing the ship Napoleon with sails and steam 
having a screw propeller, which unites in a remarkable degree rapid 
manufacturing establishment of Indret, for having calculated the theory 
of, and constructed, the mechanism of the Napoleon, and for having» in 
* In awarding the prize to M. Franchot, the Academy does not touch the q! a 
of priority as to hot-air engines, it being well known that M. Franchot in this 
has others before him. ne 
