THE NAUTILUS. 137 



Planorbis bicarinatus from the Delaware River. Sowerby, in The 

 Genera of Shells, Planorbis f. 4, Mar. 30, 1822, named and figured 

 this shell again as Planorbis bicarinatus. Amos Eaton in the Zool. 

 Text-book, p. 194, 1826, redescribes Say's species of Planorbis 

 under the generic name Helix, but his Helix bicarinatus has nothing 

 to do with Helix bicarinata Sowb., Zool. Jour., 1825, p. 58, pi. 3, 

 f. 7. 



HELIX ANGULATA Rackett (not Burrow.) 



Helix angulata Rack., Trans. Linn. Soc. London, xiii, p. 42, pi. 

 5, f. 1 (read June 1, 1819, published before 1821), was based on 

 specimens of Planorbis from Lake Huron, Canada. But this name 

 is preoccupied by Helix angulata Burrow, in the Elements of Con- 

 chology, by Rev. E. I. Burrow, London, 1815, pi. 26, f. 1, which is 

 Pleurodonte acutangula Burr. This name was also supposed to be 

 preoccupied, but Planorbe anguleux Brard, Ann. du Mus. Hist. Nat. 

 xiv, p. 435, pi. 27, f. 23, 24, 1809, was not Latinized by him. It is 

 merely a French name for another shell. 



PLANORBIS ANTROSUS Conrad. 



Described in American Journal of Science and Arts, New Haven, 

 xxv, pt. 2, p. 343, Jan. 1, 1834, from Randon's creek near Clai- 

 borne, Alabama, is therefore the first name which can be used for 

 the freshwater shell generally known as Planorbis bicarinatus Say. 

 The next name is Planorbis engonatus Conrad, New Fresh Water 

 Shells of the United States, Appendix, p. 8, pi. ix, f. H, Oct., 1835, 

 based upon the same species of shell from Albany, New York. 

 Planorbis angistoma Hald. Monogr. Fresh Water Moll. U. S., no. 

 7, Planorbis, p. 7, Jan. 1, 1844, is according to Mr. Walker, 

 Nautilus, xxiii, p. 5, probably typical antrosus. If this is a distinct 

 form Conrad's name is earlier. 



PLANORBIS BICARINATUS MAJOR Beck. 



H. Beck in the Index Moll., p. 118, 1837, lists the name Planorbis 

 bicarinatus Say, and divides it into two forms: a. major, from the 

 Schuylkill River and refers to Sowb. Genera, iv, f. 4. (Mr. E. R. 

 Sykes in the Proc. Mai. Soc. London, vii, p. 194, Sept., 1906, states 

 that part iv, of Sowb. Genera was published on March 30, 1822), 

 and to Wood, Index Test. Suppl. vii, 12, Planorbis angulatus Wood. 



b. minor, New Jersey, citing with a question Planorbis ebur- 

 neus Chemn., ix, 1123 ? from the West Indies, as a synonym. 



