186 PEOF. H. F. BAKER ON CERTAIN LINEAR DIFFERENTIAL EQUATIONS, ETC. 
matrix whose elements are power series in £, and Q(<f>) is calculated in regard tor 
from a matrix 
</. = / c.Jili,e a (tli 
while y is a matrix of constants. Here 6,, 0 2 , ..., c 12 , c 13 , ... depend solely on the 
invariant factors of the matrix A. 
This result is obtained from the form of the matrix u as expressible by powers of £, 
without reference to the question of periodicity. It would seem that the argument 
there employed is capable of modification, the integrations being performed in regard 
to t (which is log t of the paper referred to), so as to lead to the general theorem 
here contemplated. 
presented 
/ JAN. WW 
