I04 LAND AND FRESH WATER MOLLUSKS 



Bulinus hordaceus Tryon, Mon. Fw, Univ. Moll. U. S., p. 170, pi. vii, fig. 

 19, 1872. 



Range. — Oregon, Washington, Vancouver Island. 



Fort Vancouver, Wash. ! near Puget Sound, Wash. ! 



This is the small species, having much the appearance of an Aplexa.^ 

 which has been cited on the authority of Dr. J. G. Cooper as Aplexa 

 hypnorum from near Puget Sound. This error w^as afterward cor- 

 rected by Cooper himself. No observations have been recorded in 

 regard to the animal, and when these have been made it is entirely pos- 

 sible that the creature may turn out to be an Aplexa. It is entirely 

 distinct from A. hypnorum at any rate 



Genus Aplexa Fleming. 



Bulla (sT^.) Linn6, Syst. Nat., ed. x, p. 727, 1758. — Gmelin, Syst. Nat., vi, 



p. 3428, 1792. 

 Planorbis (sp.) O. T. Muller, Hist. Verm., 11, p. 169, 1774. 

 7«ri5^ (sp.) Walker, Test. Min. var., p. 15, 1787. 

 <^Bulinus O. T. Muller, in Der Naturforscher (Halle), xv, p. 6, 1781 (after 



Adanson, Senegal, p. 5, 1757, non binomial). 

 <iPhysa Draparnaud, Tableau, pp. 31, 52, 1801 ; Hist, des Moll, de France, 



p. 55. 1805. 

 <^Bulitnus PoiRET, Coq. Fluv. et Terr., p. 41, 1801 ; not of Scopoli. 

 <^Bullinus Oken, Lehrb. d. Naturg., pp. x, 302, 18 15. 

 Aplexa Fleming, in Sowerby, Gen., fasc. vii, 1822 ; Hist. Brit. An., p. 276, 



1828. Ty^c Bulla hypnorum Umrxt, 1758. 

 <iPhyza Risso, Hist. Nat. Eur. Men, iv, p. 96, 1826. 

 Nauta (Leach, MS.) Turton, Man., p. 129, 1831 (in syn.). — Leach, Syn. 



MolL Gt. Brit., p. no, 1852. 

 <^ Bulinus Beck, Index Moll., p. 116, 1838 ; not Bulinus Beck, op. cit., p. 



117, nor Philippi, Handb. Conch., p. 255, 1853. 

 Pkysa FiTZiNGER, Syst. Verz., p. no, 1833 ; not of Draparnaud. 

 AplexusGYiK\, Turton's Man., ed. 11, p. 255, 1840. — Sowerby, Man., ed. 



11, p. 70, 1842. — Brown, 111. Conch. Gt. Brit., p. 135, 1844. — Chenu, 



Man., I, p. 481, 1859. 

 Aplexa ^"E-CVi, Index Moll., p. 116, 1838. — Philippi, Handb. Conch., p. 255, 



1853. — Morch, Vidensk. Meddel., p. 308, 1864. — Tryon, Struct. Syst. 



Conch., Ill, p. 103, 1884. 

 Nauta Beck (in syn.), Ind. Moll., p. 166, 1838. 

 Amplexa Brown, 111. Conch. Gt. Brit., ed. 11, p. 31, 1844 (err. type); not 



Amplexus Brown, op. cit., p. 45. 

 Aplecta Herrmannsen, Ind. Gen. Mai., I, p. 65, 1846. — Fischer, Manuel 



Conch., p. 511, 1883. 

 Myxas Gray, Proc. Zool, Soc. for 1847, p. 180, not of Leach, 1822. 

 Bulinus BiNNEY, Land and Fw. Sh. N, Am., li, p. 97, 1865. — Dall, Ann. 



Lye. N. Hist. N. Y., ix, p. 356, 1870. 

 Nauta Westerlund, Fauna Pal. Reg., v, p. 57, 1885. 



Shells of species allied to Pkysa., but usually more slender and 

 elevated, the mantle not extending beyond the margin of the aperture 

 and its edge entire, without filamentary appendages ; jaw strongly 



