RISSOID^. 49 



11. Hydrotaia achaja. 



Hydrobia achaja, Clessin, MalaJc. Bldt. XXV, 1S78, Etiboea. 

 8 Eubcea ; ex " Linnsea" and P. Bouvier, Esq. 



12. Hydrobia thiessese. 



Hydi'obia Thiesseas, Clessin (ubi 1). 



8 Euboea ; ex " Linnaaa" and P. Bouvier, Esq. 

 Seems to me scarcely separable from the preceding. 



13. Hydrobia aponensis. 



Hydrobia aponensis, von Martens, Wiegm. Arch. 1867, Ahano, for Paludhnt 

 thermalis, Kilster, Sfc. {not of Lin.) ; sect. Thermhydrohia. 



3 Abano (Padua) ; ex " Linnaja" (as " Hydr. thermalis, Lin."). 



Subgenus BYTHINELLA, Moquin-Tandon. 



J. de C. 1851, p. 239, and Hist. Moll. 1856, type Bulimus viridis, Poiret ; 

 sect. = Belyrandia, Bourg., Moll, quart. Seine, 1869, type £. gihba Brap.; 

 sect. = Vitrella, Clessin, 1877, type P. pellucida, Benz ; sect. = Frauen- 

 feldia, Clessin, 1879, type F. lacheineri^ Clessin ; sect. = Maresia, Bourg., 

 Bull. Soc. Toulouse, 1877, type Hydr. dolichia, Bourg.; sect. = Stimpsonia, 

 Clessin, Mai. Bldt. XXV, 1878. 



Dr. Kobelt joins the sections Maresia and FrauevfekUa ; but 

 if this is adopted, the former name must have priority. M. de 

 Eolin has suggested tliat the group Vitrella may be the same 

 as his Locardia ; M. Bourguignat considers them as distinct : 

 if they prove identical, both names must yield priority to M. 

 Bourguignat's genus Lhotelleria, which is unmistakeably the 

 same as Locardia. 



14. Hydrobia (Bythinella) obtusa. 



Paludinella obtusa, Lea, Trans. Am. Fhilos. Soc. IX, 1844, Ohio ; sect. 

 Stimpsonia. 



2 New York ; coll. Prof. E. C. Stearns. 



15. Hydrobia (Bythinella) binneyi. 



Pomatiopsis Binneyi, Tryon, P. Philad. Ac. 1803, Bolinas, California ,• 

 ? sect. Stimpsonia, 



20 Baulincs Bay ; coll. Prof. E. C. Stearns. 



