1887] Zoology. 87 
The Hyoid Structure in the Amblystomid Salamanders 
My attention was recently called by my friend Dr. Eleanor Galt 
to the fact that the figures of the hyoid apparatus of Amblystoma 
punctatum given by Drs. Parker and Wiedersheim are not cor- 
rect. The latter (“Das Kopfskellet der Drodein. ” pl. v. f. 75) rep- 
resents the hypohyal tha as forming the posterior parts of 
a cartilaginous circle, from which two recurved processes on each. 
side extend, the anterior spfitouchin g the ceratohyal, the pos- 
terior returning towards the basibranchial. Parker omits the 
annulus altogether. Now, as Dr. Galt points out, there is a car- 
tilaginous ring which supports the circumference of the tongue 
in this genus in a manner different from anything known in any 
other genus of Batrachia. But it is not connected in any way 
with the hypohyals, but issues from each side of the basi- 
branchial, posterior to them; and supports the tongue above the 
basibranchial level. It sends out one lateral process on each 
side (Fig. 1) which does not connect with the ceratohyals. 
On examining other species of Amblystomidæ, Dr. Galt found 
the same character present in A. talpoideum, A. opacum, A. tigri- 
num, and A. macrodactylum. In A. tenebrosum she found a very dif- 
i 3 
Fig. 1, Amblystoma punctatum X 2, thiir below. Fig. 2, iaidó tenebrosus 
1, from below. Fig. 3, Linguelapsus annulatus, X 2, 2, from above CH, Cerato- 
hyal ; HH, hyphohyal; OH; otohyal; BB1, first basi- branchial ; BB2, second basi- 
branchial; CBr, first cerato-branchial ; CB2, second cerato-branchial ; EB, epi- 
branchial. 
ferent seudan, There is no annulus, but its basal part remains in, 
the form of a plate on each side of the middle line, the external 
angle of which represents the external process of the ri ng of Am- 
blystoma punctatum. To the straight anterior border of this cartil- 
age is attached a sheet of fibrous tissue, the fibres being distinctly — 
antero-posterior in direction, and forming the basement tissue of 
the tongue. The cartilage, handle-like in this species, and ring-like 
in the A. punctatum, is not homologous with any of those which 
have received names, so I propose to call it the otoglossal cartilage. 
These observations of Dr. Galt induced me to examine some 
of the other species referred to serena bei aise: I report the fol- 
