46 PROCEEDINGS OF THE NATIONAL MUSEUM. 



vol. 59. 



Occurrence.-Ripley Formation. Dave Weeks place on Coon 

 Creek, McNairy County, Tennessee. 



CoUection.-V. S. National Museum (Cat. No. 32461) . 



Outside Distribution.-Ripley Formation, Lees Mill, Mississippi. 

 Selma Chalk, Mississippi, Alabama, Georgia. 



HAMULUS, species. 



Plate 10, figs. 3, 4, 5. 



Operculum small and fragile, consisting of a circular disk and 

 an elongate three-cornered posterior process or apophyse; circular 

 disk marked on both the anterior and posterior sides of lines radiat- 

 ing from the center; margin of disk slightly serrate; position of 

 anophyse on the disk eccentric. 



This species of operculum is known from a single mdmdual which 

 was found detached from a tube. It is most likely hat it belongs 

 either to Hamulus squamosum Gabb or Hamulus angulatus, probably 



^cuZnce.-Bipley Formation. Dave Weeks place on Coon 

 Creek, McNairy County, Tennessee. 



CoTlection.-V. S. National Museum (Cat, No. 32462). 



EXPLANATION OF PLATES. 



Plate 9. 



Fig 1 Operculum of Hamulus onyx Morton. X 10, front view. 

 " 2 Operculum of Hamuhcs onyx Morton. X 10, basal view. 



3 Operculum of Hamulus onyx Morton. X 10, rear view 



4 sipula corUortuplicata, a recent operculate Annelid, figure taken from 



Nicholson and Lydekker. 0. ^operculum. 



5. Hamulus onyx Morton. X 4, side view. 



6. Hamulus onyx Morton. X 4, basal view showing operculum in P lace . 



7. Hamulus deformis (d'Orbigny). X 4, side ™"> £™*f* c pecimen 



from the Cenomanian, Le Mans, France (Cat. ^o. 32463 U.S.N.M.). 



8. Same as figure 7. X 4, apertural view. 



Plate 10. 



Fig 1 . Hamulus angulatus new Bpecies. X 4, side view. 

 2 Same as figure 1. X 4, apertural view. 



3. Operculum of Hamulus, species. X 10, front view. 



4. Operculum of Hamulus, species. X 10, basal view. 

 b. Operculum of Hamulus, species. X 10, rear view. 

 6 Hamulus squamosus Gabb. X 4, side view. 



I Srri^H^' X 4, «. .... -*.* o„„ - a. *_ 



axial depressions. 

 9. Same as figure 8, X 4, apertural view. 

 10 HamuZui 8 ej>tm*ufcato Reich and Cotta, a species common in the Oeno 



manian of Saxony. Figure taken from Wanderer 

 U. Scrpula crassa Sowerby an operculate annelid from the Eocene of England, 

 figure taken from L. Agassiz. 



