dall: groups of bulimulus 121 



nodule on the pillar and an inward projection on the middle of the 

 outer lip. The axis is thin, slender and twisted except in the last whorl 

 and usually has a purple stain on it not visible from the aperture. 

 The figures named simrothi in my monograph of 1900, are really taken 

 from specimens of tortuganus, a correction made possible by the re- 

 ceipt of authentic specimens of simrothi. 



This group initiates the series of species with apertural armature 

 which renders the group of NaesioUis so peculiar. 



Group of N. wolfi (Ochsneria n.). 



A'^. akanatus Dall. A^. alethorhytidus Dall. 



N. adelphns Dall. N. cymaiias Dall. 



N. wolfi Reibisch. N. ochsneri Dall. 



N. lycodus Dall. A^ saeronius Dall. 



This group is confined to Indefatigable Island, and is a denizen of 

 the arid zone though occasionally found on trees during the rainy season. 

 The form is short and stout, the surface more or less corrugated, in 

 some species to an extraordinary extent; there is a strong nodule on the 

 pillar, another on the body, both usually more or less prolonged as a 

 ridge into the interior of the last whorl; and sometimes one on the outer 

 lip. A^ saeronius is one of the smallest of the Naesioti. All the species 

 are unusually solid. 



Group of A^. duncanus (Granitza n.). 

 A^. duncamis Dall. 

 A^ jervisensis Dall. 

 A^ darwini Pfeiffer. 

 These species are found on James, Jer\ns, Duncan, and possibly 

 Bindloe Islands. The shells are large, thin, short, with feeble tubercu- 

 lations on the pillar, bod}^ and outer lips. The upper part of the axis 

 is very slender and twisted. Only N. darwini has been found living. 



Group of A^. sculpturaUis (Granella n.). 

 N. sctdptiiratiis Pfeiffer. 

 A^. rabidensis Dall. 

 A^. nigiferus Sowerby. 

 A^. naesioiicus Dall. 

 N. reibiscki Dall. 

 N. nudus Reibisch. 



These forms are known from James, Rabida (or Jervis) and Inde- 

 fatigable Islands. The doubtful N . nudus is reported from Charles 

 Island. They are irregularly axially ribbed, sharply spirally striate, 

 granulose and corrugated, slender and thin, with unarmed aperture, 

 slender and more or less solid twisted axis and numerous whorls. They 

 indicate the transition from the more normally formed species.toward the 

 peculiarly shaped Pleuropyrgus. 



Group of A^ chemnitzioides {Pleuropyrgus Martens). 

 A^. chemnitzioides Forbes. 

 A^. lima Reibisch. 



