736 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvn. 



Plate XLVII. 



Limipecien tcxanu,s, p. 722. 



A specimen somewhat larger than the type, retaining both valves in conjunction. 



Fig. 1. Left valve. The anterior ear is better i^reserved than in tig. 1 of Plate XLV, 



and the figure shows how abruptly it is depressed below the rest of the shell. 



The finer surface ornamentation has been lost by weathering or abrasion. 



2. Right valve. The difference in surface ornamentation is well shown. 



3. Side view of both valves. The convexity of the left valve has been some- 



what exaggerated by fracture, but it is evidently much greater than that 

 of the right. The depression of the anterior ear in this valve (left) and 

 its sharp demarcation from the rest of the shell are clearly represented. 



Clavulitcs hoirardensis, p. 732. 



Fig. 4. Enlargement of an imperfect specimen to show the surface. The A'entral 

 side is represented. It did not prove to be practicable to show upon the 

 concentric ridges the crenulations which, by reason of their linear succes- 

 sion, give well preserved surfaces the appearance of being marked by 

 delicate, discontinuous longitudinal line. 



5. View of the dorsal side of a specimen iu which the callosity is strongly 



marked. 



6, 7, 8. Ventral, dorsal, and side views of a strongly curved specimen in which 



the callosity is faint. 

 9,10,11. Dorsal, ventral, and side views of a more nearly straight specimen in 

 which the callosity is again prominent. 



