19 AI.DRTCH, Eocene Mollusca 19 



lot. This species is named after the late Dr. W. Langdon, an 

 Assistant State Geologist of Alabama and the discoverer of the 

 Floridian Miocene. 



Semele monroensis, n. sp. PI. 2. Figs. 21, 22. 



Shell small, rather flat ; one right valve only in the collec- 

 tion ; umbonal slope strongly bent ; surface smooth above with 

 several widely spaced lines towards the ventral margin ; hinge 

 stout ; ligament long for the genus ; the umbonal slope marked 

 interiorly by a few radial lines. Length 5 mm. 



Locality. — Bell's Landing, Ala. River, Ala. 



Type. — Ala. Museum of Nat. History. 



Remarks. — The specimen described is quite young but dis- 

 tinct. Looks like a Meretrix in shape and ornamentation. 



Lucina primoidea, n, sp. PI. 2. Figs. 23, 24. 



Shell with manj^ raised lines ; beaks recurved, higher than 

 long. This species is figured because it is from an horizon close 

 to the Cretaceous and is doubtless an ancestral form of Lucina 

 cornuta Gonr. of the Claibornian. The interior is not accessible. 



Locality. — Black Bluff, Tombigbee River, Ala., about 20 feet 

 above the base. 



Type. — My collection. 



Martesia recurva, n. sp. Pi. 2. Figs. 25, 26. 



Shell small, short, rotund ; with two accessory plates just 

 forward of the umbones ; groove running nearly vertical from 

 beaks to base and strongly marked ; concentric striae strongly 

 marked on the posterior end, bending abruptly at the groove and 

 thence running up behind the umbones and under the accessory 

 plates ; the anterior end rounded and smooth ; cardinal margin 

 bordered with a thickened and raised process. Length 8 mm. ; 

 height 4^ mm. 



Locality. — Fleming's Mill, Ala., on Pea River. Nanafalia 

 beds. 



Type. — My collection. 



Remarks. — This species is more obtuse than the usual forms. 

 Three examples found. The interior is not accessible. 



