Box 25, Folder 6: Paleontology II

Tellenomya ovata Hall

Wis. Geol. Rep. 1861 p 28

Description. Shell ventricose, sub = ovate; cardinal line straight or very little curved; anterior end broad, obliquely truncate; posterior end short, narrow; basal margin broad rounded, a line drawn from its junction with the anterior and posterior slopes passes across the middle of the shell; beaks small, not prominent, curved, directed towards the anterior end. Valves gibbous at the anterior and attenuate at the posterior end; the length, breadth & thickness of the valves when compared are seven, six and five. Surface of shell smooth or marked by a few concentric lines of growth of moderate strength

This species resembles T. nashuta; but the beaks are more nearly central and the posterior end is not produced in the same manner. The basal line is regularly curved and does

The basal line is regularly curved and does not show the contraction on the posterior side of the middle of the base which is observed in that species.

Geological Formation and Locality. In the Trenton group, (Buff limestone,) Beloit, Wisconsin.

Collector. Edward Daniels.

Hall Geol. Rep. Wis 1861 p. 27

Also Vol 1 p 38 fig 3, & p. 438

Ill. Geol. Rep 3 p. 307 pl 2 fig 7. a. b. c

TELLINOMYA VENTRICOSA, ^ (n. s.)

Description. Shell sub-rhomboidal, extremely ventricose, with strong incurved beaks, the anterior dorsal and ventral margins sub-parallel, the posterior and obliquely truncate, the anterior end broadly rounded, and continuing into the basal margin; posterior umbonal slope somewhat angular, with a slight sulcus just anterior to it, which passes from near the beak of the base. Surface marked by obscure concentric striae of growth.

28

The interior is marked by large, double, profoundly deep muscular impressions; the principal scars are abruptly depressed on the inner margins, the minor scars faintly marked except on old individuals. The hinge plates are of medium width and contain about eight or ten slightly curved teeth on the anterior side of the beak, and from twelve to fourteen on the posterior side; beaks (in the cast) rather distant. The internal cavity of the shell is deep.

This species somewhat resembles T. contracta (Ctenodonta contracta, Salter, Canadian Organic Remains, Decade I, pl. 8 fig. 4 and 5); but differs in the greater proportional length greater breadth of the anterior end, and greater obliquity of the posterior slope. The shell is more ventricose, the beaks nearest to the posterior end (instead of the anterior) and the muscular impressions more deeply marked.

Geological Formation and Locality. In rocks of the age of the Trenton limestone group; the buff limestone at Beloit, Janesville and Mineral Point, Wisconsin; at Dubuque Iowa, the Falls of St Anthony, and other places.

Collectors Prof. Nason, E. Hobart & James Hall.

Mt Carrol Ill. Galena Limestone

Beloit

Mineral Point

Dubuque

St Anthony's Falls.

Tentaculites? flexuosa Hall

Pal. NY Vol 1 p 92 pl 29 fig 6

Cin Shale SW of SE Sec 24 T.7 R. 18

Waukesha Co.