NATURAL SCIENCES OF PHILADELPHIA. 203 
laterals. The marginals figured are from the portion of the mem- 
brane where they are the least developed as to their cutting points. 
H. Hazard (pl. VIII., fig. 5) has 16—1—16 teeth with 8 laterals. 
Hi. oppilata. Not examined. 
H. Dorfewilliana. Not examined. 
H.. Ariadne. Not examined. 
H. septemvolva (pl. VIII., fig. 6) has 9 laterals. I cannot 
count the teeth or draw the marginals on the only slide I have 
preserved. The latter were described by me as being like those 
of fastigans. After an opportunity of examining the true sep- 
temvolva at St. Augustine, I give a more detailed figure on pl. 
XX., fig. 5. There are 28—1—28 with 9 laterals. The small 
form with five whorls differs only in having somewhat fewer teeth. 
The form known as #. volvowxis does not differ excepting in having 
fewer marginals: Jacksonville, Fla., specimens have 20—1—20 
teeth. 
H. cereolus. Too late for illustration, I have received specimens — 
collected at Key West by Mr. W. W. Calkins. There are 22—1—22 
teeth, with 9 laterals all of same type as in septemvolva. 14 ribs 
on jaw. 
Hi. Carpentertana. 22—1—22 teeth, with 9 laterals, 12 ribs on 
jaw. ? 
H. Febigert (pl. VIII., fig. 7) has 17—1—17 teeth with 9 
laterals. 
Hf. pustula (pl. VIII., fig. 8) has 17—-1—17 teeth with 8 laterals. 
H. pustuloides. Not examined. 
H. ieporina. ‘Too late for inserting in the plates, I have re- 
ceived through Mr. Bland, the jaw and lingual membrane of a 
Texas specimen furnished by Mr. A. G. Wetherby. The jaw has 
11 ribs. There are 18—1—18 teeth, with 8 laterals, all of same 
type as in H. fastigans. 
Subgenus POLYGYRELLA. 
Jaw of the only known species, Helix polygyrella (pl. XVI., 
fis. 11) very low, wide, very slightly arcuate, ends very gradually 
attenuated: cutting margin without median projection: anterior 
surface with numerous (even 26), broad, slightly separated ribs, 
denticulating either margin. | 
Lingual membrane (pl. [X., fig. 2) long and narrow. Teeth 27 
—1—27, with 5 perfect laterals. Centrals subquadrate, the lower 
lateral angles but little expanded; the upper margin broadly 
