NO. 2 NEW TURRITID MOLLUSKS BARTSCH 3 



whorl is lost ; the remaining nuclear turn appears to be smooth. The 

 early postnuclear whorls are marked by protrac-tively slanting, axial 

 ribs, of which 9 occur upon the first three turns and 10 upon the fourth. 

 On the first three whorls these axial ribs are quite regular, being 

 strongest on the middle of the turns and tapering toward the summit 

 and the periphery. The spaces that separate them here are about as 

 wide as the broad ribs. On the fourth postnuclear whorl they begin to 

 be more oblique and tend toward the formation of a lamina at the tip. 

 This becomes accentuated on the fifth turn, and on the succeeding 

 turns it becomes increasingly more pronounced, gradually forming 

 the broad winglike expansion that characterizes this species. There 

 are 10 ribs on the fifth and sixth, 8 upon the seventh to ninth, and 

 12 upon the last turn. These alations are marked by incremental lines, 

 and their outside, as well as the base and columella, are crossed by 

 slender, wavy, spiral threads. The insides of the alations are smooth, 

 barring incremental lines. Aperture moderately large and expanded, 

 decidedly channeled anteriorly and at the posterior angle. Outer lip 

 thin, protracted between the posterior channel and slender stromboid 

 notch anteriorly. Inner lip reflected over the somewhat twisted colu- 

 mella as a heavy callus, which extends over the parietal wall and 

 forms a slight lump near the posterior angle. 



Type. — The unique type, U.S.N.M. no. 430852, was dredged at 

 station 12, ofif the north coast of Puerto Rico, in 200 to 300 fathoms 

 between latitude i8°3i' N., longitude 66°oo'i5" W. and latitude 18° 

 3o'3o" N., longitude 66°oi'45" W. It has 11.5 whorls remaining and 

 measures: Length, 31 mm; greater diameter, including alations, 

 19.7 mm. 



FENIMOREA, n. gen. 



Type species. — Feniiiiorea janetae, new species. 



Shell large ; nuclear whorls well rounded, smooth. Postnuclear 

 whorls with strong, broad axial ribs that are retractively bent and re- 

 duced in the depressed groove below the summit and extend anteriorly 

 to the fasciole on the base. The finer sculpture on the ribs and inter- 

 costal spaces consists of decidedly wavy incised spiral lines and fine 

 incremental lines, which vary in strength. The combination of these 

 two elements gives to the surface a peculiar efifect, resembling the 

 scales on some butterfly wings ; this sculpture extends to the basal 

 fasciole. The fasciole itself and the area immediately posterior to 

 it, as well as the rest of the columella, are marked by spiral threads. 

 The aperture is moderately long and broad and strongly channeled an- 



