Herrick, WVerves of Siluroid Fishes. 195 
the pseudobranch of the cod may be supplied either by the 
communis IX or communis VII or both. Further than this 
only degeneration experiments will show. In the plaice we 
learn from the blood vessels that the pseudobranch zs a hyozdean 
ademtibranch but nothing more. Further, that it is supplied by 
the IX nerve (mostly) and also perhaps by VII zs absolutely 
certain. Let us suppose, therefore, that the pseudobranch of 
the plaice and cod is a posterior demibranch on the hyoid arch. 
Then Jacosson’s anastomosis (there being otherwise no pre- 
trematic IX in the plaice) is the pre-trematic IX (+ palatinus 
also?), and your pre-trematic VII is the post-trematic VII. 
Further, when STannius and PaRKER refer to the IX supplying 
the pseudobranch, they are referring to JACOBSON’S anastomosis, 
and surely they are also right.’’ Of course, if the teleostean 
pseudobranch proves to be, as here suggested, a hyoidean 
demibranch, rather than mandibular, then the posterior palatine 
must be the post-trematic branch of the facialis, if it is a 
branchial nerve at all. It will accordingly, be safer to avoid 
the term r. pre-trematicus VII in this connection until the mor- 
phology of the pseudobranch is more definitely known in a 
larger series of teleosts. Mr. Coe in this same correspondence 
calls attention to an error in my memoir on the cod fish (oo, 
p. 287), where it is stated that Jacosson’s anastomosis runs 
from the facialis to the glossopharyngeus. Of course it is to 
be expected theoretically that these fibers would take the op- 
posite course, if these commissural fibers represent (as I be- 
lieve they do) the palatine branch of the glossopharygeus. 
Renewed examination of my sections of Gadus indicate that 
his criticism is sound in fact, as well as in theory, for the evi- 
dence is that these fibers do arise from the IX ganglion and 
run forward. I was misled by the fact that the apparent size 
of the commissural nerve diminishes rapidly as it passes caudad 
from the junction with the facialis. In Ameiurus there is no 
JacosBson’s anastomosis, though the palatine branch of the 
glossopharyngeus is very large and extends cephalad in the roof 
of the mouth near the median line nearly as far as the level of 
the foramen of exit of the posterior palatine. The latter nerve, 
