416 S. W. RANSON AND P. R. BILLINGSLEY 
Third thoracic white ramus, 23 fibers 6u in diameter or larger. 
There were no very large fibers like those in the two preceding 
rami. 
Fourth thoracic white ramus, 10 fibers 6y in diameter or greater. 
No very large fibers. 
Fifth thoracic white ramus, 24 fibers 6u in diameter or greater, 
of these 2 measured 13n. 
Sixth thoracic white ramus, 73 fibers 6u in diameter or greater, 
the largest of which measured 10x. 
Seventh thoracic white ramus, 109 fibers 6u in diameter or 
larger. There were no fibers of 10 to 13 diameter. 
Eighth thoracic white ramus, 101 fibers 6u in diameter or 
greater. None of them very large fibers. 
Ninth white ramus, contained 174 large fibers, but many of 
them were a little under 6x in diameter. 
Tenth white ramus. In this specimen we found a direct ramus 
to the tenth thoracic ganglion and a descending ramus to the 
eleventh. The direct white ramus contained 130 large fibers, 
one of which measured 10u; the descending white ramus in this 
case consisted very largely of fibers 6 to 8u in diameter, 106 in 
number. The total number of large fibers coming from the tenth 
thoracic nerve was thus 236. 
Eleventh thoracic white ramus. Here again we found a direct 
and a descending white ramus and in both together there were 59 
large fibers. 
Twelfth thoracic white ramus, 11 large myelinated fibers, of 
which the largest was 8x. ' 
Thirteenth thoracic white ramus, 56 large myelinated fibers. 
While these white rami did not all come from a single animal— 
the first was from one cat, the second to the fifth from another, 
and the sixth to the thirteenth from a third cat—the results 
have been checked on a sufficient number of other cats to show 
that the larger differences between the rami of the several levels 
are significant. The greatest outflow of large fibers occurs 
through the seventh to the tenth or eleventh white rami, inclusive. 
Figure 3 shows the relatively large number of them in the tenth. 
