THE NATURAL HISTORY SURVEY. 281 



Distribution: Joliet, Illinois ( Ferriss) ; Saginaw River, Mich. 

 (Walker). 



Habitat: Same as reflexa. 



Remarks: This variety was erroneously identified as atten- 

 uata Say in a paper on Limnaea in the St. Louis Academy. Mr. 

 Bryant Walker called the writer's attention to this error and 

 suggested its description as a new variety, characterized by an 

 attenuated spire, rounded whorls and a general scalariform as- 

 pect. It is fairly common at Joliet, but has not been found in 

 any other part of the area. 



Jolietensis has a close resemblance to variety kirtlandiana, 

 but in the former the whorls are more rounded, increase more 

 rapidly in size and the last whorl is differently shaped. The 

 varieties scalaris, kirtlandiana and Jolietensis are very closely re- 

 lated but seem to be easily distinguished. 



ii2b. Limnaea reflexa walker! Baker, pi. xxxi, fig. 2. 



Limnaa reflexa var. scalaris BRYANT WALKER, The Nautilus, Vol. VI, 

 p. 33, pi. i, fig. 7, 1892. 



Not scalaris VAN DEN BROECK (Ann. Soc. Mai. Belg., Vol. V, p. 

 37, pi. ii, fig. 1, 1870, Vol.vii, p. 89, 1872), a variety of Limnaa 

 stagnalis. 



This form is intermediate between the typical reflexa and the 

 variety Jolietensis. It is in reality a scalariform condition, the 

 whorls being well rounded and divided by a deep suture. The 

 variety does not seem to be very common, and is always found, 

 at least in this area, associated with the type. It may be col- 

 lected sparingly in Lake Calumet and near Joliet. 



Length, 37.00; width, 11.00; aperture length, 12.00; width, 6.00 mill. 

 28.00; " 9.00; " " 10.00; " 5.50 " 



M2c. Limnaea reflexa kirtlandiana Lea, pi. xxxi, fig. 4. 



Limncea kirtlandiana LEA, Proc. Amer. Phil. Soc., Vol. II, p. 33, 1841. 



"Shell: Turreted, thin, irregularly striate, pale horn color, 

 imperforate; spire attenuated; sutures impressed; whorls six, 

 slightly convex; aperture narrow-elliptical. Diameter, .26, 

 length .70 of an inch." (Lea.) 



A number of shells answering in a general way to Lea's 

 description were collected by the writer in Mud Lake, near 

 Grand Crossing. They are small, none of them exceeding 

 four-fifths of an inch in length. The whorls seem to be more 

 rounded in some individuals than Lea's figure (Binney, Fig. 

 in) would indicate, but aside from this they agree very well. 

 In some specimens the outer lip is thickened within by a heavy, 



