EASTMAN : CARBONIFEROUS FISHES FROM THE CENTRAL WEST. 225 
Fig. 37. Deltodus contortus (St. J. and Worth.). Lower Carboniferous limestone ; 
Visé, Belgium. Posterior dental plate referred to the right ramus of 
the lower jaw, viewed from the postero-lateral margin, X 4. 
Fig. 38. Deltodus: occidentalis Newb. and Worth. Keokuk limestone; Keokuk, 
Iowa. Posterior dental plate referred to the right ramus of the lower 
jaw, X 4. 
Fig. 39. Phoebodus dens-neptunt, sp. nov. Keokuk limestone; Keokuk, Iowa. 
Outer coronal face, x #4. 
Figs. 40,40 a. Phoebodus knightianus, sp. nov. Florence Flint, Chase formation 
(Permo-Carboniferous); Blue Springs, Gage County, Nebraska. 
Lateral and anterior aspects of imperfect crown, showing prominent 
projection of the base in the median line in front, x 4. 
Fig. 41. Deltodus spatulatus Newb. and Worth. Keokuk limestone; Keokuk, 
Iowa. Posterior dental plate referred to the right ramus of the lower 
jaw. 
Fig. 42. Deltodus spatulatus Newb. and Worth. Burlington limestone ; Burlington, 
Iowa. Posterior dental plate referred to the right ramus of the lower 
jaw, Xt. 
Fig. 43. Deltodus contortus (St. J. and Worth.). Coronal surface of same specimen 
as shown in Fig. 87, X 4. 
The originals of Figs. 35-43 are preserved in the Museum of Comparative 
Zoology ; the single tooth represented in Figs. 82-34 belongs to the United States 
National Museum. 
_ PLATE 5. 
Fig. 44. Physonemus pandatus, sp.nov. Kinderhook limestone ; Burlington, Iowa. 
Lateral aspect of spine, X 1. 
Fig. 45. Physonemus hamus-piscatorius, sp. nov. Kinderhook limestone; Burling- 
ton, Iowa. Lateral aspect and cross-section of exserted portion of 
spine, X 4. 
Fig. 46. Physonemus hamus-piscatorius, sp.nov. Kinderhook limestone; Burling- 
ton, Iowa. Exserted portion of spine in lateral aspect, with rugose 
distal extremity, and a portion of the substance removed by fracture, 
exposing tubular pulp-cavity, X }. A tooth of Helodus biformis N. and 
W. is imbedded in the same block of limestone in immediate juxtaposi- 
tion to this spine. 
Fig. 47. Erismacanthus barbatus, sp. nov. Kinderhook limestone; Burlington, 
Iowa. Fragmentary spine with rudimentary anterior branches, 
i 
Fig. 48. Coelacanthus exiguus Eastm. Coal Measures; Mazon Creek, Grundy 
County, Illinois. Complete individual of average size, 4. 
Fig. 49. Elonichthys perpennatus Eastm. Coal Measures; Mazon Creek, Grundy 
County, Illinois. Complete fish, probably of a young individual, 
with downwardly flexed caudal fin, fine fulcra on the pectorals, 
and impressions of the axis showing through the delicate squamation, 
x £. 
Fig. 50. Tuberculated dermal plate belonging to an undetermined Elasmobranch. 
Kinderhook limestone ; Burlington, Iowa, x }. 
VOL. XXXIX. — NO. 7 5 
