14 
MUSEUM BULLETIN No. 31. 
Class, Brachiopoda Dumeril. 
Genus, Pseudolingula Mickwitz. 
Pseudolingula iowensis (Owen). 
Plate Y, figures 1, 2. 
Lingula ioivensis Owen. Geol. Rep. Iowa, Wis., and 111., 1844, p. 70, 
Pl. 15, fig. 1. Por further synonymy, see Bassler, Bull.. 92, 
U.S. Nat. Mus., pt. 2, 1915, p. 729. 
Since this shell, which is rather common and widespread in the 
Ordovician of Iowa and Minnesota, has not previously been indenti- 
fied from the more eastern Trenton, the opposite valves of a fairly 
well preserved specimen have been figured. 
Locality . The species has been found in Ontario only in the 
upper part of the middle Trenton at Trenton, Ont., where it was 
collected by E. J. Whittaker and the writer. 
Genus, Dalmanella Hall and Olarke. 
Dalmanella rogata (Sardeson). 
Plate Y, figures 5, 6. 
Orthis rogata Sardeson. Bull. Minn. Acad. Nat. Sc. 3, 1892, p. 331, 
PL 5, figs. 1-4. Am. Geol. 19, 1897, p. 95, PL 4, figs. 1-10. 
Dalmanella testudinaria Hall and Clarke ( partim ). Pal. N.Y., 8, 
pt. 1, 1892, Pl. 5B, figs. 27-31, Winchell and Schuchert, Pal. 
Minn., 3, pt. 1, 1893, p. 441, Pl. 33, figs. 17-22. 
Orthis and Dalmanella testudinaria ( partim ) of many authors, 
including most references to specimens from thse American Trenton. 
It has been customary to call most of the American middle and 
upper Ordovician Dalmanellce , Dalmanella testudinaria, but it is now 
admitted that the so-called species is capable of subdivision though 
no one seems to have proved that the real Dalmanella testudinaria 
is found in America. 
DalmanV figures are very poor, though not so bad as the repro- 
duction in volume 8 of the Palaeontology of New York. Fortunately 
the Museum of Comparative Zoology contains three specimens of 
this species collected in 1832 by Marklin at the type-locality at Boren- 
shult, Oestergotland, Sweden. A photograph of the opposite valves 
of the best specimen is presented here (Plate V, figs. 3, 4). The shell 
l Kong. Vet. Acad. Handlingar, 1827. Reprint of 1828, p, 31, Pl. 2, figs, 
4a-e. 
