62 SCALARIIIXE. 



angulated in front, umbilical region filled by a twisted funicu- 

 lum. Operculum corneous, few-whorled, with subcentral nucleus. 

 Europe, West Coast of Africa, West Indies, 



Indian Ocean, Japan. 

 Smithia, Maltzan, 1883, is a synonym. 



This genus has usually been arranged with the family Turri- 

 tellidse. 



Genus ACLIS, Loven, 1846. 



Animal with long, retractile proboscis, tentacles close together 

 at the base, slender, cylindrical, eyes sessile at their external 

 bases ; foot truncate ; mentum narrower than the sole, and 

 extending far beyond the head ; operculigerous lobe ample, 

 unsymmetrical. Radula of numerous, simple, aculeiform teeth. 

 Shell narrowly umbilicated or rimate, small, turreted, subulate, 

 smooth, or usually with spiral riblets ; aperture oval, entire, the 

 peristome not continuous, lip thin, simple. Operculum corneous, 

 thin, ear-shaped, paucispiral, with marginal nucleus. 



Aclis resembles Turritella in form, but is much smaller and 

 umbilicated. A few living forms are found in European seas, 

 and a dozen fossil species, commencing with the Devonian, are 

 also referred to the genus. 



Ebala (Leach), Gray, is a synonym. 



Section ACLIS (sensu stricto). 

 Shell spirally sulcate. 



Section HEMIACLIS, Sars., 1818. 



Shell smooth, spire elongated, a little conical, apex regular, 

 obtuse; base a little dilated, aperture rather large. 



Section GRAPHIS, Jeffreys, 18 6 f. 



Cylindrical, longitudinally striated or reticulated ; spire elon- 

 gated, apex obtuse and twisted ; aperture oval, contracted. 

 Cioniscus, Jeffreys, 1869, is a synonym ; the earlier name was 

 unnecessarily changed on account of being preoccupied in 

 lichens. 



Section PHERUSA, Jeffreys, 1869. 



Shell subcylindrical, smooth, subperforate ; apex obtuse, 

 twisted, but not sinistral ; aperture angulated at the base, lip 



