170 J. B. JOHNSTON, 
C. J. Herrick (99) describes a spinal VIII tract as follows 
(p. 205): “The VIII nerve and probably also the three lateral line 
roots send root fibres caudad, thus constituting the spinal VIII tract. 
These fibres form two close round bundles lying at the periphery of 
the oblongata. The sensory root of the vagus emerges just dorsally 
of them (fig. 17, sp. VIII). Immediately caudad of the level here 
figured they turn ventrad, forming external arcuate fibres to cross 
in the extreme ventral portion of the raphe. This decussation oc- 
cupies the extreme ventral surface of the brain for almost the entire 
extent of the region of the lobus vagi.” The ground for calling this 
a spinal VIII tract seems to be that it is a descending tract. It 
certainly is not homologous with the descending root of the VIII 
in man, since that root accompanies the spinal V to end in a nucleus 
on the mesial side of the nucleus gracilis (KOELLIKER, 96, p. 256; 
CaJAL, 96, p. 61—64). HERRICK is certainly right in saying that 
this tract is probably not homologous with the spinal VIII as described 
by me in Acipenser. This tract I described (98b, p. 585) as follows: 
“Mesial to this nucleus [Nucl. fun. et trig. sp.|, and imperfectly 
separated from it, is a second collection of cells which is the ter- 
minal nucleus for part of the fibres of a large bundle which runs 
backward parallel with the spinal V from the tuberculum acusticum. 
The large size of the bundle suggests that it is made up mostly of 
lateral line fibres. As indicated in figs. 1—3, the greater part of 
the fibres of this bundle end in the same nucleus with the spinal V, 
but I have not found spinal V fibres entering the smaller median 
nucleus. This bundle and nucleus are apparently homologous with 
the spinal VIII and its nucleus of human anatomy.” I regret that 
my statement did not make it clear that this tract is composed of 
root fibres, most of which belong to the lateral line nerve. HER- 
RICK has been misled by this and says (99, p. 206) that this tract 
“appears from the description to be made up largely of secondary 
fibres from the tuberculum acusticum, and not, as here, and as in 
human anatomy, of direct root fibres”. I hope the ambiguity is 
entirely eliminated from the present description (page 75). HERRICK 
goes on to homologize my spinal VIII with a secondary VIII tract 
described by him (p. 206) which lies deep in the medulla and runs 
to the cerebellum, while my spinal VIII runs to the caudal 
end of the medulla. I have no doubt that the spinal VIII in 
Acipenser is homologous with that of human anatomy, while HER- 
RICK’s is not. I know of no fibres in Acipenser which could be 
