FISHES OF THE CARBONIFEROUS SYSTEM. 95 
like that represented in Fig. 4, but rounded below and with coarser orna- 
mentation, like that of Fig. 8, which is a copy of a portion of a central plate 
of the carapace, found in the same region, but said by Mr. Lilley, from 
whom I received it, to have come from the Chemung rocks. 
GANORHYNCHUS BEECHERI, N. sp. 
Plate XIX, Fig. 2. 
Head terminating anteriorly in a massive bony arch, of which the under 
surface is rounded and covered with a thick sheet of polished enamel, marked 
with pits of irregular size and distribution, the mouths of calcigerous tubes. 
Of this bone the anterior face is vertical, the under surface flatly arched 
from front to rear, the posterior face transversely straight in the middle, on 
the sides excavated to form two large rounded notches, perhaps the nasal 
apertures. 
This interesting specimen apparently represents the labial margin of 
the upper jaw; a strong bony arch firmly anchylosed to the head, and 
covered with polished but porous enamel, forming a powerful dental organ, 
fitted for crushing mollusks or crustaceans. It is evidently generically 
identical with, but specifically different from, a peculiar and unique speci- 
men found without labeF or history by Dr. Henry Woodward among 
the material inherited by the South Kensington Museum from the British 
Museum, and described by Dr. R. H. Traquair’ with the name of Ganorhyn- 
chus Woodwardi. The resemblances and differences between that specimen 
and the one before us will be apparent on comparing the figures now given 
with those which accompany the article referred to. 
Dr. Traquair compares his specimen with the nasal extremity of the 
head of Dipterus, and gives apparently good reasons for considering it the 
labial margin of the upper jaw of a Dipnoan fish allied to Dipterus, Ctenodus, 
and Paledaphus. It is even possible that both the specimen described by 
Dr. Traquair and that now under consideration are the anterior and pre- 
maxillary elements in the dentition of some species of Cfenodus ; since the 
extremity of the head of Ctenodus is not known, and the labial margin of the 
upper jaw in Dipterus is so similar. 
1 Geol. Mag., vol. 10, London, 1873, p. 552. 
