THE NAUTILUS. vii 



Sitala hangchowensis Pils., n. sp 5 



Sphaerium from Illinois, a new . . . . . 21 



Sphaerium hendersoni Sterki, n. sp 69 



Sphaerium, on the pathology of 11 



Sphaerium solidulum 11 



Sphaerium stamineum forbesi Baker, n. var. . . .21 

 Stenotrema altispira Pilsbry (PI. V, figs. 5-7). . . Ill 

 Stenotrema brevipila Clapp, n. sp. (PL V, figs. 1-4). . 110 

 Stenotrema from Alabama, new species of ... 109 



Strigilla carnaria 1 



Subspecies, mutations and forms . . . 58 



Tellina (Eurytellina) angulosa. ... 1 



Tivela mactroides 3 



Tomogeres Montf 11 



Tonicella blaneyi Dall 62, 65 



Tonicella ruber var. index Balch, n. var. . . 66 



Traehydermon ruber. ... ... 62 



Unionidae, some observations on the ova of . 68 



Unionidae of Kansas. . . . 144 



Valvata bicarinata Lea (PI. I, fig.14) . .29 



Valvata bicarinata connectans Walker, n. var. . 30 



Valvata bicarinata perdepressa Walker, n. var. (PI. I, 



figs. 15-16). . 30 



Valvata, notes on ... 25 



Valvata lewisii Currier (PI. I, figs. 12-13 . 29 



Valvata sincera danielsi Walker, n. var. (PI. I, figs. 10, 



11) . ... .28 



Valvata sincera Say (PI. I, figs. 1-6) . . . .26 

 Valvata sincera nylanderi Dall (PI. I, figs. 7-9) . 28 



Vitrea approxima and V. vanattai, note on . . 57 



Vitrea (Paravitrea) aldrichiana Clapp, n. sp. (PI. V, figs. 



8-11) . ... .109 



Volutidae, a review of the American . . . 129, 142 

 Ward, Henry A. (obituary) ... .48 



Winkley collection of shells 118 



Wisconsin shells, list of .... 



Zonitoides alliaria in Colorado. . . 144 



