ONYCHODONTIDiE. 
393 
attenuated in the distal half, firmly fixed to the supporting hone, 
and with a relatively small internal cavity ; the teeth diminishing 
rapidly in size downwards in the series. 
Form. Sf Log. Lower Old Red Sandstone: Herefordshire. 
Fig. 52. 
Onychodus anglicus, A. S. Woodw.—Presymphysial dentition, side view 
(partly in section), twice nat. size. [Oxford Museum.] 
P. 6252. The inferior portion of a presymphysial hone, exhibited 
in vertical section in matrix, shown of twice the natural 
size in PI. XY. fig. 1; Bush Pitch, Ledbury. 
Presented by George H. Piper , Esq., 1890. 
The following species are also known only by remains of the 
presymphysial dentition, of which there are no examples in the 
Collection :— 
Onychodus circticus, A. S. Woodward, Rep. Brit. Assoc. 1889, 
p. 585, and Geol. Mag,. [3] vol. vi. (1889), p. 499.— 
L a J^ er Devonian ; T ^pitz^ergen. [Royal State Museum, 
Stockholm.] 
Onychodus liopkinsi , J. S. Newberry, Rep. Geol. Surv. Ohio, 
vol. i. pt. ii. (1873) p. 302, and Palaeoz. Fishes N. America 
(Mon. U. S. Geol. Surv. no. xvi. 1889), p. 99.—Chemung 
Group (Upper Devonian) ; Delaware Co., New York. 
Onychodus ortoni , J. S. Newberry, Palaeoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 71, pi. xix. 
fig. 1.—Huron Shale (Upper Devonian); Franklin Co., 
Ohio. 
An undetermined species, as large as the type, also seems to be 
indicated by some robust, sigmoidally curved teeth from the Devo¬ 
nian of Gerolstein, Eifel, Germany, preserved in the Museum of 
Comparative Zoology, Cambridge, Mass., U.S.A. 
