PLANOBRBIS. 399 
The specimen in the Berlin Museum, acquired from Godeffroy, agrees very well with 
Clessin’s description and figure, but not so well with the description of Tryon, who 
gives only three whorls. 
16. Planorbis panamensis. 
Planorbis panamensis, Dunker, P. Z. S. 1848, p. 41°; Sowerby, in Reeve’s Conch. Icon. xx. 
Planorbis, t. 12. fig. 95. ' 
A very small shell, with rapidly enlarging whorls and deeply excavated left side. Diam. 3 millim. 
oy. 
Hab. W. Panama: Panama, in small streams (coll. Cuming 12). AS 
Ye 
Only known to me from the description and figure. 
Subgen. SPIRALINA. 
Spiralina, Hartmann, Gasteropoden d. Schweiz, i. tab. (1840) (sine descr.)*. 
Spirorbis, Swainson, Treatise of Malacology, p. 337 (1840) (nec Spirorbis, Daudin, 1800, 
Annulata). 
Gyrorbis, Moquin-Tandon, 1855 (part.); Kobelt, Catalog d. europ. Binnenconch. p. 57 (1871) ; 
Clessin, Deutsche Excursions-Mollusken-Fauna, 1884, p. 412 (nec Gyrorbis, Fitzinger, 
subgen. of Valvata, 1833). 
Diplodiscus, Westerlund, Act. Soc. pro Fauna et Flora Fenn. xiii. p. 218 (1897) (nec Diplodiscus, 
Diesing, 1850). 
Shells of moderate or small size, with 5-8 gradually increasing whorls, more or less 
sharply keeled at the periphery, flatter on the left side than on the right; surface 
with faint strie of growth, not very shining. Aperture broader than high, lanceolate 
or asymmetrically rhomboidal. | 
European (P. vortex, L., &c.) and Tropical-American. 
17. Planorbis cultratus. 
Planorbis cultratus, d’Orbigny, in Ramon de la Sagra’s Hist. fis. polit. y nat. de Cuba, Moluscos, 
p. 105, t. 14. figg. 5-8 (1845?)*; v. Mart. Binnen-Mollusken Venezuela’s, p. 4, t. 2. 
fig. 107; Reeve, Conch. Icon. xx., Planorbis, t. 18. fig. 106°; Fisch. & Crosse, Miss. 
Scient. Mex., Mollusca, ii. p. 68, t. 32. figg. 7, 7 a, 6, ¢*; Clessin, in Martini & Chemnitz, 
Syst. Conch.-Cab. ed. 2, Limnziden, p. 148, t. 22. fig. 3°. 
Planorbis duetasianus, Tristram, P. Z. 8. 1861, p. 232°. 
Planorbis kermatoides (d’Orb.), Tate, Am. Journ. of Conch, v. p. 158 (1870) ’. 
* Spiralina was used by Hartmann only as a “ nomen nudum,” without description or indication of species ; 
but as he has distinguished all the other European subgenera of Planorbis by different names in the same 
work, itis clear that he recognized this group, a fact verified by myself when examining his collection in the 
Museum at St. Gallen in 1890, where P. depressus, Mich., a variety of P. vortex, and P. leucostomus, Millet 
(a species nearly allied to P. vortex), are labelled with the name Spiralina. Gyrorbis ae wrongly ageribed to 
Agassiz by Kobelt and Clessin, the latter quoting even a page in the paper of Charpentier (1887 ), in which, 
however, the name Gyraulus (not Gyrorbis) is to be found; it was first proposed by Moquin-Tuntou [ Moll. 
Terr. et Fluv. Fr. p. 428 (1855)] for a section of Planorbis comprising P. carinatus, P. marginatus, P. vortex, 
and P. spirorbis, but the name is preoccupied by Fitzinger (1883) for a subgenus of Valvata. 
50* 
