260 SMITH. 



EXPLANATION OF PLATE A. 

 Schloenbachia oregonensis Anderson. 



Figs. 1-3. Protoconch, phylembryonic to ananepionic. -^y"-. 



Figs. 4 and 5. Phylembryonic to paranepionic ; diameter 0.58 mm. ; one-half 

 whorl, first eight septa, glyphioceran stage at the sixth. -*/. 



Fig. 6. Paranepionic, glyphioceran substage ; diameter 0.64 mm. ; third to tenth 

 septa, five-eighths of a whorl. ^^. 



Figs. 7 and 8. Phylembryonic to paranepionic, glyphioceran substage; diameter 

 0.68 mm. ; three-quarters of a whorl, nine septa. -*j^-. 



Fig. 9. Paranepionic, glyphioceran substage ; diameter c.74 mm.; seven-eighths 

 of a whorl. ^-. 



Figs. 10 and 11. Paranepionic, transition from glyphioceran to gastrioceran 

 substages; diameter 1.20 mm.; one and three-eighths whorls. -\°. 



Figs. 12 and 13. Paranepionic, transition from glyphioceran to gastrioceran 

 substage; diameter 1.33 mm. ; one and five-eighths whorls. \"-. 



Figs. 14 and 15. Paranepionic, gastrioceran substage; diameter 1.65 mm.; one 

 and seven-eighths whorls. ^-. 



