NO. I2 PERMIAN BRACHIOPODS FROM OREGON—COOPER By, 
Interior of pedicle valve unknown except for the presence of a 
subperipheral marginal thickening. 
Measurements in mm.—Holotype, surface length 18, length 11.1, 
hinge width 13.0+, length of visceral area and trail about equal (9 
each), height 7.0. 
Types.—Holotype, U.S.N.M. 124156a; figured paratypes, U.S.N.M. 
124157, 125533, 126981a; unfigured paratypes, U.S.N.M. 124156b, 
126981b. 
Localities —638; S12, S49; U.O. 2201-2, 2204-1. 
Discussion—This interesting little productoid is unique among 
American species in having the median trough anterior to the visceral 
area and in having a long carinate trail. The only productoid like it 
is Proboscidella? kutorgae Tschernyschew (1902, p. 643, pl. 50, 
figs. 1-3) from the “Schwagerina” limestone of the Urals. The 
Russian species differs from the Oregon one in its larger size, finer 
and more abundant reticulation, and in the absence of the strong 
carina on the trail. Nothing at present is known of the interior of 
the Russian species. 
PLEUROHORRIDONIA? ELONGATA Cooper, new species 
Plate 7C, figures 30-33 
Large, narrowly elongate; hinge slightly narrower than the width; 
cardinal extremities auriculate, ears small and rounded. Beak in- 
curved but not protruding beyond the posterior margin; umbo nar- 
row, sulcate; sulcus deep, widening and deepening anteriorly but 
narrow throughout the shell length. Flanks narrowly and strongly 
rounded; sides steep; surface smooth on the posterior third but 
longitudinally and irregularly costellate on the anterior two-thirds. 
Brachial valve unknown. 
Measurements in mm.—Holotype, length 40.5, midwidth 31.4, 
maximum width 33.2, surface length 80, hinge width 26.6. 
Type.—Holotype, U.S.N.M. 125346. 
Localities —S47, S51, S87; U.O. 2205-5. 
Discussion.—This species is difficult to place, and few good speci- 
mens are available for study. The posterior or umbonal region ap- 
pears to be quite smooth but the trail and steep lateral slopes have 
numerous longitudinal subdued ribs. These also appear in the deep 
and narrow sulcus. The only genus like this is the newly erected 
Pleurohorridonia of Dunbar. The Oregon specimens are not char- 
acteristic of the genus because they are much narrower and the ears 
of the cardinal extremities are not so extended. Unfortunately, the 
