3AN o 1895 
The N AUTILUS. 
VOL. VIII. JANUARY, 1895. 
No. 9 
TWO NEW PISIDIA. 
BY DR. V. STERKI. 
PI. II, Figs. 1-13. 
Pisidium cruciatum, n. sp. Figs. 1-6, 13, 13a. 
Shell minute, inequipartite, oblique, subtriangular in outline, 
high, ventricose, regularly and comparatively coarsely striated, 
straw colored; anterior part moderately long with an oblique, 
nearly straight edge above and the end rounded ; posterior part 
short, the end somewhat obliquely truncate, superior margin rather 
strongly curved, scutum scarcely, scutellum little marked, the latter 
forming a rather distinct angle; inferior part moderately curved ; 
beaks prominent, each with two ridges diverging at nearly right 
angles, together forming a cross on the upper aspect of the shell, 
each of the ridges ending in a nodule of which the posterior is 
larger and more prominent; nave rather thick, whitish; hinge 
very stout, list strong ; cardinal teeth rather large, and strongly pro¬ 
jecting inward from the hinge list; in the right valve one, strongly 
curved, posterior part thick, anterior thin, lamellar, the ends united 
by a lamella so as to form a deep groove into which the posterior 
tooth of the left valve articulates; in the left valve two, the poste¬ 
rior (inferior) stout, massive, the other, superior and a little anterior, 
rather short, fine, lamellar, oblique, little curved ; lateral teeth 
large, high and pointed in the left, strongly projecting inward in 
