602 EDWARD PHELPS ALLIS, JR. 
The hyomandibula of these descriptions of Edgeworth’s is the 
similarly named cartilage (Ph) of both Firbringer and Kra- 
wetz. The ventro-lateral one of the two pieces said to be cut 
off from the auditory capsule is certainly the symplectic (Hx) of 
Krawetz and the dorso-mesial one the dorsal process (Ja) of the 
hyomandibula (Ph) of the latter author’s descriptions. That one 
of these two authors should consider these two cartilages to have 
been cut off from the auditory capsule while the other consid- 
ers them to have been developed wholly independent of the 
capsule, is evidently simply a difference of interpretation of the 
same phenomena. Edgeworth says that the two cartilages lie 
‘external’ to the nervus hyomandibularis facialis, without saying 
whether the nerve issues anterior or posterior to them. But, as 
he compares one or both of the cartilages with the hyomandibula 
of Huxley’s descriptions of the adult, it would seem that one of 
them, at least, and probably both, were considered by him to 
lie posterior to the nerve. This agrees with what both Sewert- 
zoff and Krawetz say of the cartilage (Hx) but is the exact oppo- 
site of what Krawetz says of his little dorsal process (Ja). 
Greil (13), in the latest work published on this subject, makes 
no reference to either Krawetz’s or Edgeworth’s earlier works, 
and hence had probably not seen them when his own was sent to 
press. In an embryo of Stage 47 he describes and figures (l. ¢., 
p. 1293) a small cartilage, lying internal to the nervus hyoman- 
dibularis facialis, which he calls the epihyal or hyomandibula. 
This little cartilage is the hyomandibula (Ph): of Firbringer, 
Krawetz and Edgeworth, and is said by Greil, as it was by Kra- 
wetz, to be a serial homologue of theepibranchials. These latter 
cartilages are said by Greil (p. 1239) to be directed postero-mesi- 
ally from the dorsal ends of the ceratobranchials, instead of an- 
tero-mesially as the epibranchials invariably are in all other 
gnathostome fishes, and as the dorsal ends of the ceratobran- 
chials are shown (fig. 23, pl. 61) curving dorso-antero-mesially 
in the usual position of an epibranchial, comparison with my 
descriptions of the adult seems to me to conclusively show that 
the so-called epibranchials of both Greil’s and Krawetz’s descrip- 
tions are pharyngobranchials, and that the epibranchials have 
