672 proceedings of the academy of [dec, 



Reference to Plates XXI-XXVII. 

 Plate XXI. — Figs. 1, 2.^Helicina schereri n. sp. 

 Fig. 3. — Helicina guajarana n. sp. 

 Figs. 4, 5. — Helicina laterculus n sp. 

 Figs. 6, 7. — Guppya mayi, n. sp. 

 Figs. 8, 9. — Strobilops braziliana n. sp. 

 Fig. 10. — Leptinaria imperforata n. sp. 

 Fig. 11. — Leptinaria perforata n. sp. 

 Figs. 12-14. — Zonitoides par ana n. sp. 



Plate XXII. — Figs. 1, 2. — Solaropsis rugifera Dohrn. 



Figs. 3, 4.—Happia snethlagei n. sp. 



Figs. 5-7. — -Streptaxis cookeana n. sp. 



Figs. 8~10. ^AStreptaxis abunaensis n. sp. 



Figs. 11-13. — -Eiitodina jeckylii n. sp. 



Figs. 14, 15. — Systrophia eatoni n. sp. 



Figs. 16, 17. — Diplfldon obsolescens n. sp. 



Fig. 18. — Orlhalicus sultana meobambensis Pfr. 



Fig. 19. — Psadara derbyi cearana n. subsp. 

 Plate XXIII. — Figs. 1-4. — Drymceus branneri n. sp. 



Figs. 5-8. — Drymoeus linostoma suprapunctatus n. subsp. 



Figs. 9, 10. — Tomigerus ]iilsbryi n. sp. 



Figs. 11, 12. — Odontostomus inflatus costulatus Anc. 



Figs. 13, 14. — Buliinulus rochai suturalis n. subsp. 



Figs. 15, 16. — Odontostomus scabrellus cylindricus n. subsp. 



Fig. 17. — Buliinuliis rnrhai taipuensis n. subsp. 



Fig. 18. — OdoNtos/oiinis infhitus maranguapensis n. subsp. 



Figs. 19, 20. — Bulimulus rochai n. sp. 



-Figs. 21, 22. — -Corona regalis Hupe. 

 Plate XXIV. — Figs. 1-7. — Doryssa transversa jaryensis n. subsp. 



Figs. 8, 9. — Doryssa transversa tapajosensis n. subsp. 



Fig. 10. — Doryssa rex n. sp. 



Figs. 11, 12. — Doryssa transversa tapajosensis n. subsp. 



Figs. 13, 14. — Doryssa transversa, var. near macapa. 



Fig. 15. — Doryssa rex n. sp. 



Figs. 16, 17. — Doryssa rex regina n. subsp. 

 Plate XXV. — Figs. 1, 2. — Doryssa globosa n. sp. 



Figs. 3, 4. — Doryssa heathi n. sp. 



Figs. 5, 6. — Doryssa starksi n. sp. 



Fig. 7. — Doryssa heathi n. sp., young shell. 



Fig. 8. — Doryssa iheringi n. sp. 



Fig. 9. — Doryssa cachoeircE n. sp. 



Fig. 10. — Doryssa cachoerioe. sulcata n. subsp. 



Figs. 11, 12. — Doryssa tucunareensis n. sp. 



Figs. 13, 14. — Doryssa starksi n. sp. 



Fig. 15. — Hemisinus flammeus n. sp. 



Fig. 16. — Hemisinus flammeus elongatus n. subsp. 

 Plate XXVI. — Figs. 1, 2, 3. — Gundlachia baker i Pils., n. sp. Dorsal, lateral, 

 and ventral views of the type. 



Fig. 4. — Gundlachia bakcri. Very young individual of non-septate form. 



Figs. 5-8. — Gundlachia bakeri. Non-septate form, dorsal, lateral, ventral, 

 and posterior views of the adult stage. 



Figs. Q-ll. —Segmentina paparyensis n. sp. 



Fig. 12. — Eupera sp. undet. 



Figs. 13, 14. — Idiopyrgus pilsbryi n. sp. 



Fig. 15. — Littoridina manni n. sp. 

 Plate XXVII.— Figs. 1, 2.—Anodontites dalli n. sp. 



Figs. 3, 4. — Anodontites bartschi n. sp. 



Fig. 5. — Diplodon kelseyi n. sp., young. 



Figs. 6, 7. — Diplodon kelseyi n. sp. 



Figs. 8, 9. — Hijrin jamauchimensis n. sp. 



