Raymond and Barton. — American Species of Ceraurus. 



PLATE 2. 



Fig. 1. Ceraurus pleurexanthemus Green. The specimen (No. 4 Coll. 

 M. C. Z.) on which figure 1 of the preceding plate was based. It 

 is from the Trenton limestone at Trenton Falls, N. Y. The 

 figure is two thirds larger than natural size. 



Fig. 2. The same species. A photograph of a specimen 8 mm. long, (No. 5 

 M. C. Z.) introduced to show the similarity of the young to the 

 adult. The specimen is from the same locality as the last, and 

 the figure is five eighths larger than the specimen. 



Fig. 3. Encrinurus rarus (Walcott). A photograph of the specimen de- 

 scribed by Walcott as Ceraurus rarus. It is from the Lower Tren- 

 ton at Beloit, Wisconsin, and is now in the Walker Museum at 

 the University of Chicago. The figure is of natural size. 



Fig. 4, 5. Ceraurus dentatus Raymond and Barton. The holotype of the 

 species, figure 4 showing the hypostoma, which is attached to the 

 doublure in its natural position. The specimen is from the 

 Trenton at Van Kleek Hill, Ontario, and has been for many years 

 in the Museum of the Geological Survey of Canada. The figure 

 is of natural size, the photograph was made by the Geological 

 Survey of Canada, and is published with the permission of the 

 Director. 



Fig. 6. Ceraurus miller anus Miller and Gurley. A pygidium from the 

 Lorraine at Cincinnati, Ohio. The specimen is No. 11 Coll. 

 M. C. Z., and the figure is one seventh larger than natural size. 



Fig. 7. Ceraurus -pleurexanthemus Green. A photograph of the test showing 

 the under surface. The specimen is from the Trenton at Trenton 

 Falls, N. Y., and is No. 6 Coll. M. C. Z. The figure is two thirds 

 larger than natural size. 



