190 CONTRIBUTIONS 



seem to have been observed by Lamarck. The figure of 

 Brogniart* is much more elevated and rounded at the apex 

 than our species. 



L. Duclosii.-\ Plate 6. Fig. 203. 



Description. Lunulites slightly convex and cellular 

 above, concave and radiate below ; cells in rows diverging 

 from the apex and from the sides of other rows ; pores be- 

 tween the lines of cells scarcely perceptible. 



Diam. .2, Height nearly .1, of an inch. 



The segment is a magnified view. 



Observations. Goldfuss gives a large figure of the radi- 

 ata (Lamarck), which resembles our species. In the 

 Duclosii, however, the rows of cells seem disposed to form 

 differently, there being one or two rows which are longer 

 than the others, and from the sides of which others again 

 diverge. I do not observe the grain of sand in the apex 

 of this species ; having but one or two specimens, I have 

 not destroyed them for the purpose of examination. 



I am not aware of more than one species of Lunulites 

 having been observed in England. The urceolata (Lam- 

 arck) is mentioned by Phillips as being found in the Chalk 

 of Yorkshire. It is also found at Grignon. Two species 

 only have, I believe, heretofore been described, radiata and 



* Desc. Geolo. des Environs de Paris, pi. 8, fig. 9. 



i Named after M. Duclos, a distinguished conchologist of Paris. 



