30 



Observations on the Terrestrial 



bidentate, inner side of larger denticle shouldered, uncini denticulated. (PL 9, 

 Fig. 76.) The entire character of dentition in this species resembles that of 

 the Valloniiiee. 



Succinea ovalis, Gould. 



Generally diffused throughout the State, though not common. 

 Found on " lily j^ads" in ponds, and on bits of wood along their 

 margin. 



Buccal plate, (Fig. 77,) similar in shape to that of S. 

 Totteniana, the folds on the cutting edge are much smaller. 

 Lingual membrane 80-40-1-40. Plates all long and slen- 

 der, lateral plates inclined outward, notched at their pos- 

 terior edges, central plate tridentate, denticles very small, 

 laterals bidentate, one large and one small denticle, imcini 

 tridentate, extreme uncini unidentate. (PI. 9. Fig. 78.) 



Heart pulsates eighty times per minute. 



PUPAD^. 



Zua lubricoidea, Stimpson. (Fig. 79.) 



Common to the State. Found oftener near the coast. 



Buccal plate, (Fig. 81,) slightly arcuate, 

 tapering to a point laterally, the cutting 

 edge produced in the centre to an obtuse 

 Fig. 81. beak ; longitudinal striae conspicuous. 



Lingual membrane 90-21-1-21, central plate long, very narrow, with a min- 

 ute central tooth, with traces of a denticle at each side of its base. Laterals 

 square, bidentate, first denticle wide and strong, as long as plate, second den- 

 ticle short, obtuse ; first seven uncini tridentate, inner denticle prominent ; the 

 rest short wide plates, denticulated, two extreme uncini plain. (PL 10, Fig. 82. ) 



The American species has been unhesitatingly referred to Zua 

 lubrica, by all European and American writers, with the exception 

 of Wm. Stimpson, who mentions it in his Synonymy of New 

 England shells under a different specific title, that of Bulimus 

 lubricoides, deeming it impossible that an introduced species could 

 have spread so generally over this continent. An attentive ex- 

 amination and comj)arison of many specimens from several differ- 

 ent localities in Europe, and from Ohio, New York, Massachusetts, 



