180 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 1888.] 



A FOSSIL LINGULA PRESERVING THE CAST OF THE PEDUNCLE.* 

 BY CHARLES D. WALCOTT. 



The known examples of the preservation of the cast of any of the 

 fleshy parts of a brachiopod in a fossil state are very few. Two only 

 have heretofore come under my notice. One is the peduncle of Eich- 

 waldia subtrigonaUs, figured by Davidson from a siliciiied specimen col- 

 lectedfrom the Black River limestone in Canada (Mong. Brit. Foss., 

 Brach., Vol. in, p. 192), and the other the peduncle of Lingulaf lesueuri, 

 figured by the same author (Vol. IV, p. 302, pi. xl, fig. 16). 



Figures 1 ami 2 are copies of the 

 original figures. 



Fig. 1. — Eichwaldia subtrigonaUs, 

 sbowiug peduncle issuing from the 

 beak of the ventral valve (after Da- 

 vidson). 



Fig. 2. — Lingulaf lesueuri, showing 

 peduncle issuing from between the 

 valves (after Davidson). 



Fig. 3. — Linyula cequalis Ha,\\, show- 

 ing peduncle extending out from the 

 ventral ? valve. 



Fig. 3. 



I''... .'. 



The specimen to which I now call your attention shows the interior 

 of the anterior portion of the ventral valve of the Lingula cequalis Hall, 

 collected near Rome, N. Y., from the upper portion of the Lorraine 

 Terrain. The portions of the shell remaining in the matrix show the 

 median ridge extending back from the divaricator muscular scar, the 

 reflex portion of the shell forming the false area and the groove for the 

 passage of the peduncle. The portion of the peduncle preserved is 

 nearly as long as the entire length of the shell. 



1 am indebted to Mr. William P. Eust, of Trenton Falls, N. Y., for 

 the use of the specimen illustrated. It will be deposited in the collec- 

 tion of the U. S. National Museum. 



Read before the Biological Society of Washington, December 3, 1887. 



