ae 
Dentition of Pulmonate Mollusks. 105 
Lingual membrane (PI. VII, fig. K) long and narrow; central teeth tri- 
cuspid ; laterals bicuspid; marginals quadrate, irregularly bicuspid, the 
inner cutting points the larger and bifid. 
Microphysa. 
Microphysa is put in Helicea by von Martens. M. minuscula 
(Terr. Moll., V), and ctrcumfirmata, Redf., both belong to Vitri- 
nea, having aculeate marginal teeth, and jaw of Zonites. MM. 
turbiniformis, Pfr., has a jaw as in Cylindrella, Bulimulus, ete., 
1. €., With numerous very delicate, distant ribs, giving the ap- 
pearance of separate plates. It would be put in Goniognatha 
of Méreh, though there are no upper triangular median plates. 
M. vortex and incrustata (see ‘Terr. Moll., V) have quadrate 
marginal teeth ; the jaw of tncrustata has numerous, crowded, 
flat ribs; that of vortex was not observed. 
Microphysa? circumfirmata, Redfield. 
Jaw not observed. 
Lingual membrane long and broad, centrals tricuspid, laterals bicuspid, 
cusps long and slender, marginals aculeate. 
From the above description it will appear that this species 
belongs to the Vitrznea rather than to the Helicea of von Mar- 
ten’s arrangement, in which latter it is classed in ‘‘ Die Heli- 
ceen” as a species of the subgenus Microphysa. I leave it here, 
not knowing what else to do with it. 
Microphysa turbiniformis, Pfr. Jamaica. Mr. Henry Ven- 
dreyes. 
Jaw (Pl. XV, fig. C) so extremely thin and delicate as to fold over on 
itself along its margin and at its extremities; very light horn-colored, almost 
transparent ; strongly arched, attenuated towards its obtuse ends ; about 
forty delicate ribs, such as are found in Cylindrella, serrating either margin 
on about the centre of the jaw isa curving line of reinforcement, somewhat 
parallel to the lower margin; the upper margin slightly incurved at its cen- 
tre; the ribs at the centre of the upper margin do not run en chevron as do 
those of Cyiindrella. 
Lingual membrane (PI. VII, fig. L) long and narrow; teeth about 25-1-25. 
Centrals large in proportion to the laterals, with a subquadrate base of at- 
tachment; three decided, separated cusps and cutting points; laterals tri- 
cuspid; marginals low, wide, with both inner and outer cusp bearing an 
oblique, broad, bifid cutting point. 
