PLATE XXIII. 
Proetus delphinulus. 
Page Ill. • 
See Plate 2.5. 
Pig-. 1. The cephalon, natural size, drawn fi-om a cast of the internal surface. 
Fig-. 2. The same enlarged to three diameters, .showing the short glabella and broad, concave border. 
The i-ight side of the glabella has been somewhat restored in this drawing. 
Ux)per Helderbei-g group, Pm't Colhwne, Province.of Ontario. 
Proetus foeliceps. 
Page 101. 
Fig. 3. An individual i-etaining the jiarts in juxtaxiosition, but ju-esei-ving the ci-ust in a fragmentary state. 
The specimen shows the general i-n-oxiortions of the s^iecies, the convex glabella and the 
glabellar furrows. 
Fig. 4. P)-ofile of the same, showing the convexity of the body. 
Coi-niferous limestone. Near Lelioy, Genesee county. 
Fig. 5. A somewhat fragmentary individual retaining the test. 
Corniferous limestone. Near LeRoy, Genesee county. 
Fig. 6. A cephalon wanting the right cheek, showing the furrows of the glabella. The drawing is made 
from an internal cast in chert. 
Fig. 7. Outline profile of the same. 
Cornifei-ous limestone. In the di-ift. Ann Arbor, Michigan. 
Fig. 8. The pygidium represented in fig. 3, showing the peculiai- markings on the internal cast of the 
axis, noticed in the descrijition of the species. An enlargement to two diametei-s. 
Proetus tumidus. 
Page 113. 
Fig. 9. The intra-sutural portion of a cephalon, showing the tumid, rapidly tapering glabella and the 
broad flat border. 
Upper Helderberg limestones. Po7't Colborne, Province of Ontario. 
Proetus canaliculatus. 
Page 107. 
See Plate 20. 
Fig. 10. The dorsal sui-face of the movable cheeks, showing their foi-m and the tei-mination of the facial 
sutures at the antei-ior mai-gin of the doublui-e. 
Fig. 11. The internal surface of the same, showing the doublure and its excavation at the bases of thd 
cheek spines. 
Corniferous limestone. Falls of the Ohio. 
Proetus (?) planimarginatus. 
Page 112. 
Fig. 12. A view of the type specimen. (Pal. Ohio, vol. i, pi. xxiii, fig. 3.) 
Corniferous limestone. Sylvania, Lucas county, Ohio. 
Proetus Haldemani. 
Page 113. 
See Plate 21. 
Fig. 13. An imperfect cephalon, retaining the crust and showing the characteristic“glabellar furrows, but 
having a strongly reflexed frontal border. Enlarged to two diametei-s. 
Devonian limestones. Rescue Hill, Eureka District, Nevada. 
Fig. 14. A pygidium of a large individual. 
Hamilton group. Long Lake, Michigan. 
Fig. 15. The type specimen represented on plate 21, tigs. 7 and 8, natural size. 
