234 PROCEEDINOS OF THE NATIONAL MUSEUM. vol.46. 



SYRNOLA THELMA, new species. 



Plate 20, fig. 3. 



Shell small, elongate-conic, smooth except for mcremental lines; 

 suture distinct, not deep; apical portion decollate; aperture narrowly 

 ovate, outer lip simple, blunt, base rounding into a strongly twisted 

 short pillar, body with no visible callus. Length of decollate frag- 

 ment (two whorls), 2; diameter, 1 mm. 



Station 6040, near Alexandria, Louisiana. Type, U. S. Nat. Mua., 

 No. 166302. 



This fragment is sufficient to show the presence of the genus and the 

 mam characteristics of the shell. 



PALUDESTRINA ALDRICm, new species. 



Plate 22, fig. 7. 



Shell small, smooth, polished, elongate, with six or more well de- 

 fined whorls ; nucleus very minute, rather blunt ; whorls with a little 

 shoulder near the suture, giving them a slightly turrited appearance; 

 there is no sculpture except faint incremental lines ; aperture ovate 

 with a contiimous, simple peristome; umbilical chink narrow, dis- 

 tmct; base a little produced and evenly rounded. Length, 4.5; 

 diameter, 1.6 mm. 



Station 6040 near Alexandria, Louisiana. Type, U. S. Nat. Mus., 

 No. 166303. 



The several forms of this genus that foUow appear to be distinct, 

 but they show a certain amount of variation also between the indi- 

 viduals, so that it is difficult to estimate the value of the differences, 

 observed. 



PALUDESTRINA PLANA Aldrich. 



Faludestrina plana Aldrich, Nautilus, vol. 24, pt. 12, p. 139, pi. 8, fig. 3, 1911. 

 Station 6132, Aldrich and Matson; station 6040, Louisiana, Matson. 



?PALUDESTRINA GEORGIENSIS Aldrich. ^ 



Amnicola georgiensis Aldrich, Nautilus, vol. 24, pt. 12, p. 139, pi. 99, figs. 4, 

 4a; pi. 10, fig. 13, 1911. 



Station 6132, Aldrich and Matson. 



The remarkable deformations to which this species submits render 

 its generic place difficult to determine. 



?PALUDESTRINA SATILLENSIS Aldrich. 



Amnicola saltillensis Aldrich, Nautilus, vol. 24, pt. 12, p. 139, pi. 9, figs. 5-11; 

 pi. 10, fig. 15, 1911. 



Station 6132, Aldrich and Matson. 



