New LameUibranchiata. — TJlrich. 101 
Formation mid locality: Lower half of the Galena at Oshkosh, 
Wisconsin, and several localities in Goodhue county, Minnesota. 
Collectors, Chas. Schuchert, W. H. Scofield, E. 0. Ulrich. 
Technophorus subacutus, n. sp. 
Plate VII, Figs. 13 and 14, 
Shell small, rather ventricose, alated posteriorly, the hight and 
length respectively as two is to three. Cardinal margin nearly 
straight, anterior end uniformly rounded, ventral edge more gently 
curved, the posterior straight and sloping backward slightly to 
the acuminate extremity of the hinge line. 
In a cast of the interior the small beak is erect, projects prom- 
inently above the hinge line, and is situated about one-third of 
the entire length from the anterior extremity. Just in front of 
the beak there is a strong and deep impression, running almost 
vertically downward. On the anterior side this slit margins a 
rather large muscular scar. Extending backward from the beak 
the cast exhibits another, but in this case very obscure linear de- 
pression. Two curved folds, the posterior one the strongest, ex- 
tend from the postero-ventral angle toward the beaks, becoming 
indistinguishable, however, about midway between the two points. 
Surface markings and* hingement unknown. 
Length 11.5 mm., hight 6.8 mm., convexity of one valve about 
2.2 mm. 
This species is intermediate between T. faheri S. A. Miller, the 
type of the genus and T. cxtenuatus, recently described by the 
author from the lower part of the Trenton shales of Minnesota. 
In the first the posterior end is shorter and produced below instead 
of above, in the second the shape is quite different and the pos- 
terior end more drawn out. A nearer congener than either of 
these, but one that is as yet undescribed, occurs at Cincinnati, Ohio. 
Formation and locality. Upper part of the limestone of the 
Trenton formation at Minneapolis, Minn. 
Museum Geol. Nat. Hist. Sur. Minn.; Reg. No. 8338. 
Technophorus filistriatus, n. sp. 
Plate vir, Figs. 11 and 12. 
Shell small, though large for the genus, compressed, witli the 
greatest convexity in the anterior half, scarcely alate posteriorly, 
the hight and length as three is to five. Beaks small, i)rojecting 
very little, slightly incurved, one-third of the entire length of 
shell from the anterior extremity. Anterior end much the widest, 
