338 
MATHEMATICS: A. B. COBLE 
Proc. N. A. S. 
and the corresponding combinant for the counter sextic 5 2 (0 rather than 
§2(0 is K—L + M—N. These four involutions all arise from any one 
by changing the signs of any two of the comitants (y0 4 > (^) 4 > 5. In 
addition to the facts derived in 10 from this set of involutions other results 
are easily read off from their simple form. For example the conic b denned 
in 7 for 52 (0 and the corresponding conic b for S 2 (0 are in a pencil with 
the conic K{r) and meet K(t) in the four points determined by (cr) 4 = 0. 
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