Dentition of Pulmonate Mollusks. 109 
Marginals quadrate, of equal width and height, with two short, wide, blunt, 
round cusps, the inner one slightly the larger. 
Thelidomus lima, Fer. Porto Rico. Mr. R. Swift. 
Jaw arcuate, ends blunt; anterior surface with seven stout ribs; a strong 
muscular attachment. 
No lingual membrane.examined. 
Thelidomus Jamaicensis, Chemn. Jamaica. V. P. Parkhurst. 
The species is placed in Liochila by von Martens, but Mr. Bland places it 
in this genus. 
Jaw thick, arcuate, ends attenuated ; anterior surface with 14 decided 
but unequal ribs, irregularly disposed and denticulating either margin. 
Lingual membrane (PI. VIII, fig. H) long and narrow, with 41-1-41 teeth; 
there are no distinct side cusps and cuttting points on the centrals and inner 
laterals. 
Thelidomus provisoria, Pfr. New Providence, Bahamas. Goy. 
Rawson. 
Jaw very slightly arcuate, wide, low, of equal height throughout to its 
blunt ends; anterior surface with 10-15 ribs, separated by irregular intervals, 
not always reaching the cutting edge, which has a broad, blunt, median 
projection. 
Lingual membrane (PI. VIII, fig. I) with 40-1-40 teeth ; the centrals and 
laterals have a distinct side cutting point. 
Eurycratera. 
Eurycratera angulata, Fer. Porto Rico. Mr. R. Swift. 
Jaw stout, dark claret-colored, low, wide, ends blunt; about seven very 
wide, very crowded ribs, bluntly denticulating either margin. 
Lingual membrane (Pl. VIII, fig. J); central and laterals with distinct 
side cutting points. 
Eurycratera crispata, Fér. San Domingo. Dr. Newcomb. 
Jaw thick, arcuate, ends blunt; anterior surface with ten stout ribs. 
Lingual membrane (Pl. VIII, fig. K). Centrals and laterals with the 
upper margin of the base of attachment produced into angles as below, with 
distinct side cutting point; middle cutting point of centrals and inner cutting 
point of laterals greatly produced. 
Polydontes. 
No jaw of this genus examined. 
Polydontes Luquillensis, Shuttl. 
Lingual membrane (PI. VIII, fig. L) as usual in the Helicide. Centrals 
tricuspid, laterals bicuspid; cusps wtih long, sharp cutting points, extend- 
