BRITISH AVONIAN CONODONT FAUNAS 127 
being both the largest and the most steeply inclined. The anterior fang is two to 
three times the basal width of the largest of the posterior denticles, and is slightly 
recurved. The anterior bar is relatively short and the denticles stand erect. The 
larger denticles of the posterior bar are separated by only 1 or 2 smaller denticles. 
The anterior lateral process is not strongly inflexed. 
Hindeodella undata Branson & Mehl 
Plate’ sx, fig: § 
1941 Hindeodella undata Branson & Mehl: 169, PI. 5, fig. 3. 
1941 Hindeodella sp. Branson & Mehl: 170, PI. 5, fig. 9. 
1953 Hindeodella undata Branson & Mehl; Hass: 82, Pl. 16, figs. 5-7. 
1956 MHindeodella undata Branson & Mehl; Elias: 108, Pl. 1, figs. 2, ro. 
1956 Hamulosodina bransoni Elias : 108, Pl. 1, fig. 4. 
1956 Hamulosodina hassi Elias : 108, Pl. 1, figs. 11, 12. 
1961 Hindeodella undata Branson & Mehl ; Higgins: Pl. 12, figs. 10, 12. 
1963 Hindeodella undata Branson & Mehl ; Bouckaert & Higgins: 17, text-fig. 3. 
Hindeodella undata Branson & Mehl ; Collinson & Druce in press, text-fig. Io. 
MATERIAL. 35 specimens : figured, X 185. 
RANGE. North Crop 3D 4-3D 22. 
DESCRIPTION. Specimens of this species are characterized by a relatively long, 
deep and straight posterior bar, the aboral margin of which is straight and sharp, and 
the sides relatively flat. The oral surface bears a series of alternating denticles which 
are acicular in general form, and discrete for the whole of their length. They taper 
sharply toa point. Larger denticles tend to be separated by groups of 2 or 3 smaller 
ones, which may be laterally offset from the denticles of the main series. The 
anterior fang is not greatly larger than the largest of the denticles of the posterior 
bar. It makes almost a right angle with the line of the posterior bar and is straight 
for the greater part of its length. The anterior inner lateral process is short and 
continuously inflexed. It bears one or more needle-like denticles on its oral edge. 
Hindeodella sp. 
Plate 29, figs. Iza, c 
MATERIAL. I specimen : figured, X 445. 
RANGE. North Crop ZLA 33. 
DEscRIPTION. A single specimen of a small distinctive hindeodellid is illustrated. 
The posterior bar is short and relatively deep and bears a series of 5 denticles which 
increase in size posteriorly. The inclination of the 4 most posterior is about 45° to 
the line of the posterior bar, but the most posterior denticle is more strongly inclined. 
The apical denticle is rounded in cross-section and the lower part is more or less erect. 
The anterior process is sharply down-flexed and continuously inflexed, so that its 
distal end makes an angle of about 45° with the posterior bar. There is a well- 
developed, elongated basal cavity below the fang and the proximal part of the 
anterior aboral process. 
