356 
CKOSSOPTERYGII. 
1876. Rhizodopsis sauroides, W. J. Barkas, Monthly Rev. Dental 
Surgery, vol. iv. p. 433, figs, lxxxii.-lxxxv. 
1876. Ortho gnat hus, W. J. Barkas, ibid. p. 530, figs, lxxxix., xc. 
1881. Rhizodopsis sauroides, R. H. Traquair, Trans. Roy. Soc. Edinb. 
vol. xxx. p. 169, woodc. figs. 1-3. 
1890. Rhizodopsis sauroides, J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. p. 161, pi. viii. figs. 5-8. 
1890. Rhizodopsis sauroides , R. H. Traquair, Proc. Roy. Soc. Edinb. 
vol. xvii. p. 389. 
Type. Scales; unknown. 
The type species ; much elongated and attenuated in the caudal 
region, attaining a length of 0*5, but usually about half this size. 
Head with opercular apparatus occupying about one-fifth of the total 
length; parietal region of cranium longer than broad, much longer 
than the frontal and rostral region ; principal jugulars about three 
times as long as their maximum breadth ; operculum as deep as broad. 
Pelvic fins arising behind the middle point between the pectoral fins 
and the extremity of the caudal; posterior dorsal fin and the anal 
of equal size, much deeper than long, symmetrical. Scales thin, 
elongate oval, obtusely pointed behind; the exposed area rhomboidal 
in shape, marked with concentric ridges when abraded. 
Form. Sf Loc. Coal-Measures : English, Welsh, and Scottish Coal¬ 
fields. - V'. c?nr 
P. 794. Head and greater portion of trunk, ventral aspect; Knowles 
Ironstone, Eenton, N. Staffordshire. Eyerton Coll. 
P. 5196-98. Six portions of head and trunk, some showing fins; 
Knowles Ironstone, K. Staffordshire. The first shows the 
ring-shaped vertebrae, and the second also the pectoral fins; 
another exhibits a large, antero-posteriorly elongated scale 
on the inner side of the base of the pelvic fins. 
Par chased, 1885. 
P. 796. Imperfect head and anterior scales ; Deep-mine Ironstone 
Shale, Longton, N. Staffordshire. Egerton Coll. 
P. 3267. Portions of head, pectoral fin, and anterior abdominal 
region, partly in counterpart ; Knowles Ironstone Shale, 
Fenton. Enniskillen Coll. 
P. 3266. Imperfect head, with pectoral fin and anterior scales ; 
Low Main Seam, Newsham, near Kewcastle-upon-Tyne. 
Enniskillen Coll. 
P. 5195. Portions of head, pectoral fin, and anterior scales; Dale- 
moor Rake Ironstone, Stanton-by-Dale, Derbyshire. 
Purchased , 1885. 
