474 THE AMERICAN NATURALIST. (VOL. XXXII. 
Recently a large amount of new material has come under 
the writer’s observation which throws light on some of these 
points and prompts the present communication. The bulk of 
this material was obtained by the writer last summer from the 
State Quarry fish-bed, as it is called, discovered by Prof. 
Samuel Calvin in the Devonian of Johnson County, Iowa, and 
described by him in the seventh volume of the Jowa Geological 
Survey Reports and elsewhere ; for the second source of supply, 
the best thanks of the writer are due to Messrs. Edgar E. 
Teller and Charles E. Monroe, of Milwaukee, Wis., who very 
generously placed their private collections of fossil fishes at 
the disposal of the Museum of Comparative Zoology, and were 
influential in securing still further donations. Lastly, the 
inexhaustible stores of this same museum were drawn upon for 
a number of undescribed European fish remains, most of which 
belong to the famous Schultze Collection purchased in 1871. 
It will be convenient to group the notes which follow under 
their proper generic headings, beginning with the typical form 
Ptyctodus. 
Pryctopus, Pander (1858). 
(1) ‘P. obliquus. — This, the type species, was illustrated by 
Pander! in two well-executed plates in 1858, as far as the frag- 
mentary Russian material would then permit. Only two of 
the figured specimens show part of the symphysial region,” 
and these were not unnaturally supposed to indicate a distinct 
species from the remainder. This mistake, however, was rec- 
tified by A. S. Woodward in his Catalogue of Fossil Fishes, 
where a diagrammatic view of the symphysis in the left lower 
jaw of an imperfect specimen is given. All of Pander’s tritors 
are of the left lower jaw, excepting Figs. 1, 3, and 11, which 
belong to the right. The orientation of Fig. 6, however, is 
doubtful. 
(2) P. major. — A dental plate considerably larger than any 
1 Pander, C. H. Die re des devonischen Systems. St. Petersburg, 
58. cit., Pl. VIII, Figs. 10, 
3 Woodward, A. S. Catalogue of the Feist Fishes of the British pres vol. ii, 
Pt. ii, p. 38. gl. 
