No. 2.] HYOIDS AND OTICS OF BATRACHIA. 299 
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between the anterior process of the former and the posterior 
process of the latter is accomplished by an intervening bit of 
ligament. The quadrate cartilage is little or not ossified in 
Froteus. The ceratohyal is not articulated at its distal end, but 
the latter is attached to the squamosal by two ligaments, the 
superior and inferior hyosuspensorials (Pl. I., Fig. 2). The at- 
tachment is higher up than in Necturus, as the ceratohyal is 
longer. 
URODELA. 
Trematodcra. 
In Cryptobranchus the columella of the stapes is directed 
forwards, and terminates in a cartilaginous stem. This is artic- 
ulated with the suspensorium of the mandible at its proximal 
part, at the line of junction between the squamosal bone and 
the quadrate cartilage. The latter is not ossified. The distal 
end of the ceratohyal is not prolonged, and it is connected with 
the distal half of the posterior border of the quadrate cartilage 
by a wide hyosuspensorial ligament. This ligament is inter- 
rupted by a subtriangular cartilage, the hyosuspensorial carti- 
lage. 
I have not examined the genus Megalobatrachus. 
Amphiumotdea. 
In Amphiuma the stapes is lateral in position, and its short 
columella is directed outwards. It is continued as a cartilage to 
the truncate posterior apex of the osseous quadrate bone, with 
which it articulates by a suture. The quadrate is extensively 
osseous. The distal extremity of the ceratohyal is long and free, 
and is connected with the middle of the posterior border of the 
quadrate by an elongate hyosuspensorial ligament. 
Apoda. 
Merrem Pseudophidia De Blainville. Gymnophiona Miill. 
In Typhlonectes (compressicaudus) the stapes is osseous, 
and is lateral in position. Its columella is short, and is directed 
forwards, and is connected by ligament with the posterior 
border of the quadrate. The distal end of the ceratohyal is 
entirely free from the manibular suspensorium. 
