THE 
AMERICAN GEOLOGIST 
Vol. X. OCTOBEK, 1892. No. 4 
[Paleontoi.ogical Notes from the Laboratory of Buchtel, Coi,- 
LEQE, No. 2.] 
THE HEAD OF DINICHTHYS. 
By E. W. Claypole, Akron, O. 
A specimen of the skull of DlnichthyH intcnnedius recently 
found by Dr. W, Clark, of Berea, 0. , has supplied details pre- 
viously unknown regarding the plates of which it was composed. 
1 propose in this note to give some account of these in connec- 
tion with a general description of the structure of the head of 
this species, all the main characters of which belong, doubtless, 
to the whole genus. 
In his admirable "Monograph of Fossil Fishes ' Dr. Newljerry 
has given (pi. lii) a small outline sketch of what, in his opinion, 
was the general form of the head and of the individual plates of 
which it was built up. This may be regarded as a condensed 
summary of what had then been discovered of Dun'chfJii/s. The 
recently found specimen, as might have been expected from the 
skill and acumen of this well known author, coincides to a very 
large extent with his figure and illustrates his familiarity with 
the structure both of the fossil and recent forms. 
The new specimen, however, corrects this diagram in a few 
points and adds others of some importance. 
In the annexed figure* I have represented the right side of the 
*Tlie line of sectioa through the orbital is placed (on the plate of 
the outside of the skull) about half an inch too far backward. 
