8 9 



MOLLUSCA OF THE GUEF OF MEXICO 



57 



Holmes, (Pleio. Fos. S. Carolina, p. 61, 1857), refer L. 

 multilineata to Conrad, (Fos. Med. Tert. Form., p. 71,. pi. 

 40, fig. 6), but that species is L. multistriata Conrad, a 

 synonym of Conrad's L. trisulcata. The only good figure 

 of this species is Dall's, (crenel/a), Proc. U. S. Nat. Mus., 

 vol. 23, pi. 39, fig. 2, 1901. 

 Distribution. — Hatteras to Cuba, 15-124 fms. Pliocene to Re- 

 cent. Gulf coast. — Recent : Ft. Barranca, St. Joseph's 

 Bay, Crooked Island, Fla. ; Horn Island, Miss. ; Galves- 

 ton, Corpus Christi, Tex. Pleistocene : Osprey, Orient, 

 Labelle and Manatee, Fla. ; Fort Morgan, Ala., well at 

 217-421 feet; New Orleans artesian well of 1856 at 546; 

 Febacher's well, New Orleans, at 1200; Lake Borgne 

 borings ; Knapp's wells, Terrebonne Parish, No, 2 at 

 1050-1190, 1 190-1430, 1434-1519,1519-1542, 1780-1790, No. 

 3 at 1150-1200, 1330-1375, 1400-1440, i443-i47°> 1 500-1525 

 feet. Pliocene : Caloosahatchie marl. 



(Parvilucina) fontis, new species. 



Plate I, Figure i 



Shell very small, suborbicular, with nearly central, rather 

 prominent, acute beaks. Lunule deep, lanceolate ; radial 

 sculpture of fine but well-marked, rounded riblets, slight- 

 ly unequal, not divaricating, and alternating with narrow- 

 er interspaces. Riblets absent from the dorsal area. Con- 

 centric sculpture of narrow, slightly raised lamellae, which 

 cross the broader riblets. The lamellae become stronger 

 over the dorsal area where the riblets are absent. Hinge 

 heavy in proportion to the shell. Right valve with a 

 strong posterior, and a weaker anterior lateral tooth, and 

 one rather prominent cardinal tooth. Inner margin of 

 shell crenulate. Length and height 4 mm. , semidiameter 

 1.5 mm. This species resembles closely Phacoides approx- 

 imates Dall, dredged in the Gulf of California at 26 fms. 

 The two species would seem to have been undoubtedly de- 

 rived from a common ancestor. 



