162 - S. WALTER RANSON 
which surrounds its cell of origin. The collateral is usually short 
and directed toward the surface of the cell but may be long and 
coiled in its course. It ends in a bulb which lies upon the surface 
of the cell from the axon of which it arose (fig. 3). The terminal 
swelling may be very large in proportion to the size of the col- 
lateral, and in some cases the latter increases in thickness as it 
approaches the end-bulbs. These bulbs take only a light stain 
with silver, appearing bright yellow. They lie upon the surface 
of the cell beneath the connective tissue capsule and produce as a 
rule a depression of the cell surface. (b) Sometimes the collateral 
is given off from the axon at some distance from its cell of origin— 
and piercing the connective tissue capsule of another cell ter- 
minates in an end bulb which lies upon the surface of this second 
cell (fig. 4). (¢) Still other collaterals run in the connective tissue 
of the ganglion and end there in bulbs surrounded by a special 
capsule. Sometimes two or three such bulbs lie together in a 
felt-work of fine fibers and the whole mass is surrounded by a 
capsule. 
Huber (’96) was the first to describe these structures but saw 
only those that fall under subhead (a). Both Cajal and v. Len- 
hossék considered that some of these fibers were fine dendritic 
branches arising directly from the cell body. On this point 
my observations agree with those of Dogiel for in every case 
where the origin could be determined they arose as collaterals 
from axons and never as fine dendrites. According to Cajal and 
Dogiel the axons of cells of this group, after having given off 
the collaterals just described, end by dividing after the manner of 
a T or Y into central and peripheral fibers. 
3. The axon of a cell of this type splits up into a number of 
branches which with or without further branching are finally 
reassembled into a single axon. In sections 18 thick it is not 
possible to see in their entirety such complicated structures 
of this sort as were seen by Dogiel in his thicker sections and 
whole mounts; but the simpler forms are often included within a 
single section. A relatively common arrangement is seen in fig. 
5. The axon divides into two fibers which may or may not be 
of equal size and which soon reunite. A somewhat more compli- 
