MOORE — ON NEW BRACHIOPODA, ETC. 



445 



Under tlie microscope tlie sliell shows a number of widely- 

 separated, circular punctuations, wMcli are arranged in longitudinal 

 lines. 



Lept^na Davidsonii. Eng. Deslongchamps. PI. xiii., figs. 21, 22. 



The figures representing the above species are taken from speci- 

 mens for which I am indebted to M. Eugene Deslongchamps, of 

 Caen. They were found in the Upper Lias of May, associated with 

 several of the species found in this country. It appears to be abund- 

 ant in Erance, and to attain larger dimensions than any other liassic 

 Leptajna. 



I have found a single dorsal valve of this species in the Upper 

 Lias of Ilminster, which though not in good condition, sufficiently 

 identifies the Leptcena Davidsonii as a British species. 



EXALANATION OF PLATE XIII. 



Fig. 1. Terelrcdella BucJcmanii, Woodward. Interior, showing the perfect loop. 



2. . Interior of shell much enlarged, showing the 



loop in its first stage. 



3. . Second stage of the loop, with a rudimentary- 

 reflected portion. 



4. . Third stage, with the reflected portion of the 



loop now enveloped. 



5. • . Perfect shell, enlarged. 



6. Terehratula maxillata, Sowerby. Young shell, enlarged. 



7. . Interior, exhibiting the loop. 



8. Terehratella furcata, Sow. and Moore. Enlarged exterior. 



9. . Showing perfect loop. 



10. . Profile of ditto. 



11. Terehratulina radiata, Moore. Perfect sheU. 



12. . Exterior of ventral valve. 



13. . Interior, with loop. 



14. ■ . Elongated variety, from Dudley. 



15. Zellania glohata, Moore. Much enlarged. 



16. . Side view of ditto. 



17. ■ . Interior of dorsal valve. 



18. Zellania oolitica, Moore. Perfect sheU, much enlarged, showing j)uuc- 



tuated structure. 



19. . Exterior of ventral valve, 



20. . Profile of sheU. 



21. Leptcena Dojvidsoni. Exterior, natural size. 



22. . Yentral valve, ditto. 



[The longitudinal lines indicate the sizes of the specimens, all of Avhich are 



enlarged.] 



(To he continued.) 



