ON NEW BRACniOPODA. 177 



EXPLANATION OF PLATE I. 



Fig. 

 1. Terelratella Bncl^manü, "Woodward. Interior, slio-ning tlie 



perfect loop. 



2. . Interior of sliell mucli enlarged, 



slio-ffingtlie loop in its first stage. 



3. . Second stage of tlie loop, Tvith. a 



riidimentaiy reflected portion. 

 4. . Thii'd stage, -nith. tlie reflected por- 

 tion of the loop noTV developed. 



5. . Perfect slieU, enlarged. 



6. Terelratula maxillata, Sowerby. Yoiing shell, enlarged. 



7. . Interior, exldbiting tlie loop. 



8. Terelratella furcata, Soav. and Moore. Enlarged exterior. 



9. . ShoAving perfect loop. 



10. . Profile of ditto. 



11. Terehratuliiia radiafa, ^oove. Perfect sbell. 



12. . Exterior of ventral valve. 



13. . Interior, Trith. loop. 



14. . Elongated varietj^, fi'om Dundiy. 



15. Zellania fflohata, liloove. Mucb. enlarged. 



16. . Side view of ditto. 



17. . Interior of dorsal yalve. 



18. Zellania oolitica, Moore. Perfect sbeU, mncb. enlarged, 

 sho^ng pimctuated striictiu-e. 



19. . Exterior of venti'al yalve. 



20. . Profile of slieU. 



21. Le])t(sna Bavidsonii, Eug. Deslongcliamps. Exterior, natu- 

 ral size. 

 22. . Ventral valve, ditto. 



The longitiulinal lines indicate the sizes of the specimens, all of 

 wliich are enlarged. 



VOL. X., 1860, PART II. T 



