186 BRITISH AVONIAN CONODONT FAUNAS 
specific rank as P. inornatus rostratus and the P. lobatus forms with the same feature 
are referred to P. lobatus inflexus. 
Polygnathus inornatus inornatus Branson & Mehl 
Plate to, figs. 4a—6c 
1934 Polygnathus inornata Branson & Mehl : 293, Pl. 24, figs. 5-7. 
1934 Polygnathus inornata Branson & Mehl; E. R. Branson : 3009, Pl. 25, figs. 8, 26. 
1938 Polygnathus inornata Branson & Mehl ; Branson & Mehl: 132, 146, Pl. 34, fig. 37. 
non 1939 ©Polygnathus inornata Branson & Mehl ; Cooper : 400, Pl. 39, figs. 11, 12 (=Poly- 
gnathus inornata rostrata). 
1944 Polygnathus inornata Branson & Mehl; E. B. Branson : Pl. 39, fig. 37. 
1949 Polygnathus inovnata Branson & Mehl; Youngquist & Patterson: 64, Pl. 17, 
figs. 4, 5, 9, 13. 
1949 Polygnathus inornata Branson & Mehl ; Thomas : 409, 411, Pl. 3, fig. 36. 
1951 Polygnathus inornata Branson & Mehl ; Youngquist & Downs: 787, 788, Pl. 111, 
figs. 17, 18 (non Pl. 111, fig. 11=P. lobata lobata). 
non 1956 Polygnathus inornata Branson & Mehl ; Bischoff & Ziegler : 157, Pl. 12, figs. 4, 5 
(=P. flabella). 
1956 Polygnathus inornata Branson & Mehl; Hass: 25, Pl. 2, figs. 14, 15. 
non 1957 Polygnathus inornata Branson & Mehl; Bischoff: 42, Pl. 2, figs. 17, 18, 20, 21 
(=P. lacinata lacinata). 
non 1957 Polygnathus inornata Branson & Mehl; Ziegler in Fligel & Ziegler: 46, Pl. 2, 
fig. 7 (=P. nodomarginata). 
1957 Polygnathus inornata Branson & Mehl ; Cloud, Barnes & Hass: PI. 5, fig. 6. 
non 1958 Polygnathus inornata Branson & Mehl; Klapper : 1089, Pl. 142, figs. 2, 3. 
1959 Polygnathus inorvnata Branson & Mehl ; Voges : 291, Pl. 34, figs. 12-16, (non Pl. 34, 
figs. 17-20 = P. lacinata lacinata). 
non 1964 Polygnathus inoynata Branson & Mehl ; Higgins, Wagner-Gentis & Wagner: 225, 
Pl. 5, fig. 29 (=P. lacinata lacinata). 
1964 Polygnathus inornata Branson & Mehl ; Rexroad & Scott 35, Pl. 2, figs. 19, 20. 
MATERIAL. 82 specimens : figured, X 353, X 354, X 355. 
RANGE. North Crop KL 16-KL 20. 
DEscrRIPTION. The platform is semi-circular in cross-section and is ornamented 
by transverse ribs, which terminate on the platform edge as low nodes. The ridges 
may break up into transverse rows of nodes. The platform is fairly flat at the 
posterior, but anteriorly it has deep troughs, separated by a nodose carina. The 
whole unit is nearly symmetrical. 
The carina is a continuation of the free blade, and runs the whole length of the 
platform, terminating at the posterior end ina point. The blade is thin and highest 
in its mid-part, the aboral outline being straight. 
Aborally the unit is keeled, the basal cavity occurring as a small pit at, or just 
posterior to, the junction of the anterior blade and the platform. The cavity edges 
tend to be thickened. 
REMARKS. Our specimens agree closely with those of Rexroad & Scott (1964). 
