234 PROCEEDINGS OF THE ACADEMY OF [1893. 



OBSEKVATIONS ON VALLONIA. 

 BY DR. V. STERKI. 



The genus Vallonia, established by Risso 1 as early as 1826, has 

 been generally accepted only of late years. It has been ranged 

 under different groups of Helix by various writers, and later 

 regarded as a subgenus. In America*, Morse 2 was the first to treat 

 it as a genus, and he was followed by W. G. Binney (Manual Am. 

 Land Shells, p. 76). 



Acanthinula Beck and Vallonia have been united by Kobelt, and 

 after him by Dr. v. Ihering 3 to form Theba, a subgenus or genus of 

 Helix. Pilsbry, in his Check-List, 4 has placed Acanthinula as a 

 section -under Patula, and Vallonia as a section under his subgenus 

 (or genus) Polygyra (Say), but subsequently 5 he regarded Vallonia 

 as a genus. 



There are a few points known of the anatomy. The absence of a 

 secondary ureter, according to Braun and Boehme, as cited by v. 

 Iheriug, 6 is characteristic. As to the genitalia, a dart sac is said to 

 be present, and there is a flagellum to the penis ; glandular mucosse 

 were not found by Lehmann or by Moquin-Tandon, as cited by v. 

 Ihering (/. c), yet appear to be present, as Pilsbry [I.e.) ranges our 

 genus under the group Belogona (" with dart sac and mucous 

 glands "). Further anatomic examinations of all the soft parts of 

 the body are necessary. My own observations are not ready for 

 communication. 



The comparatively large number of species and forms known at 

 present, all somewhat similar as to the shell and the rather charac- 

 teristic and uniform configuration of the radula and jaw, tend to 

 prove the individuality of the group as a genus, and that it is a well- 

 defined one. 



1 Hist. Nat., de l'Eur. Merid., iv, 1826. 



2 Observations on the Terrestrial Pulmonifera of Maine. Journ. Portl. Soc. of 

 Nat. Hist., 1864, pp. 4 and 21. 



3 Morphologie und Systematic des Genitalapparates von Helix. Zeitschr. f. 

 wiss. Zool., 1S92 (pp. 386-520, pi. xviii and xix) p. 480. 



4 Nomenclature and Check-List of North American Land Shells. Proc. Acad. 

 Nat. Sc. Philadelphia, 1889, pp. 191-210. 



5 Preliminary Outline of a new classification of the Helices, Ibid., 1892, p. 396. 



6 L. c. and Les relation snaturelles des Cochlides et des Ichnopodes. Bull. Scien- 

 tifique, Paris, 1891, p. 214. — Unfortunately, Lehmann, lebende Schnecken, is 

 not accessible to me. 



