VITRINA. 



135 



Doubtful Species of Zoxites. 



Zonitcs cultellatus (see Vol. IV. p. 22, pi. lxxvi. Fig. 6). This species must be re- 

 moved from our catalogue, not having again been found in and most probably 

 not belonging to our limits. 



Zonitcs Kctvberryana, Vol. IV. p. 20, is a species of the Helicca now described 

 as a new genus Gtyptostoma, q. v. 



Zonitcs aUiarius has been found in hot-houses in Brooklyn, N. Y., and Chicago. 

 It is said by Morch to be found in Greenland (Amer. Journ. Conch., IV. 29). 



Zonites Lansingi. See Microphysa. 



VITRINA, Drap. 



Animal heliciform, obtuse before, pointed behind. Mantle posterior, with an 

 anterior prolongation covering the back, and with a process or prolongation 

 which is reflected backward upon the shell. A dis- 

 tinct locomotive disk. No caudal mucus pore. 

 Respiratory orifice (i) subcentral, on the right 

 edge of the mantle, under the peristome of the 

 shell. Generative orifice (e) somewhat in the rear 

 of the right eye-peduncle. Anal orifice contiguous 

 to the respiratory orifice. 



Shell external, imperforate, pellucid, glassy, depressed. Spire short, whorls 



2-3, rapidly increasing, the last wide : aperture large ; peristome thin, often 



membranous. 



Fig. 50. 



Animal of Vitrina. 1 



Lingual dentition of V. limpida (Morse). 



F i c j aw is highly arched, ends acuminated, blunt; anterior surface smooth 

 cutting margin with a prominent beak-like median projection. I have figured; 

 the jaw of V. limpida on PI. XVI. Fig. H. I have found it to be the same in 

 V. exilis and Pfeifferi. I have not examined either jaw or lingual membrane 

 in V. AngeliccB. 



Fig. 50 gives a general idea of the lingual membrane. The centrals have a 

 quadrangular base of attachment, longer than broad. The reflection is short, 

 with three distinct cusps, the median long and slender, bulging at the sides, the 

 outer ones very short ; all the cusps bear cutting points in proportion to their 

 length. The lateral teeth are arranged in straight transverse rows. They are 

 like the centrals, but unsymmetrical by the partial suppression of the inner 



1 From Moquin-Tandon. 



