STERKIA. 



49 



According to Boettger, who described a specimen received 

 by Pfeiffer from Crosse, the two small, deeply placed palatal 

 folds were overlooked by Crosse. Boettger gives the follow- 

 ing' description: 



The shell is sinistral, narrowly perforate-rimate, oblong- 

 ovate, subventricose, thin, rather glossy, corneous-yellow. 

 Spire convexly conic, the apex rather acute. Whorls 4^, a 

 little convex, regularly increasing, parted by an impressed 

 suture, nearly smooth, the last about f of the total length, 

 somewhat tapering at, base, at the aperture lightly 2-pitted 

 and encircled with a distinct annular callus [crest] colored 

 like the shell. Aperture subvertical, somewhat heart-shaped, 

 4-toothed. Parietal compressed, rather deeply placed, lamelli- 

 forni; columella straight, and narrow, truncate and quasi- 

 iiniplicate at base; palatals 2, parallel, not very strong, re- 

 mote, the lower very deeply placed. Peristome with a long 

 interruption, somewhat thickened, the outer margin somewhat 

 inflexed and slightly produced angularly. Length 1.75, diaui. 

 1 mm. 



Genus STERKIA Pilsbry. 



Xterkia PILS., Nautilus, XI, Feb. 1898, p. 119. 



The shell is minute (l l /o to 2 mm. long, of 4 1 / to 5y 2 

 whorls in known species), perforate, cylindric with very 

 short apical cone and obtuse summit; thin, brown, slightly 

 wrinkled or rib-striate. Aperture about as wide as long, the 

 peristome expanded or reflected, brown, thin, terminations 

 remote ; angular and parietal lamella? long, not connected, the 

 angular running to the posterior termination of lip ; colu- 

 mellar lamella and 2 palatal plicae present. 



Type, 8. calamitosa (Pils.). 



Distribution, Southern and Lower California, and from 

 southern Florida to Guatemala and Guyana. 



These minute, blunt-topped Pupillids have much the ex- 

 ternal appearance of the Old World genus Truncatellina, but 

 they differ in apertural armature. The teeth show relation- 

 ship with Ptychala-a and Nesopupa, genera now mainly living 

 on the Pacific Islands and Oriental Region, but in the middle 

 Tertiary also in Europe, associated with Gastrocopta and 

 other Holarctic genera. Though paleontologie evidence is 



