﻿356 CR0SS0PTEKYG1I. 



1876. Rhizodopsis sauroides, W. J. Barkas, Monthly Rev. Dental 



Surgery, vol. iv. p. 433, figs, lxxxii.-lxxxv. 

 1876. Orthognathics, 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. 



P. 794. Head and greater portion of trunk, ventral aspect ; Knowles 

 Ironstone, Penton, N. Staffordshire. Egerton Coll. 



P. 5196-98. Six portions of head and trunk, some showing fins ; 

 Knowles Ironstone, N. 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. 



Purchased, 1885. 



P. 796. Imperfect head and anterior scales ; Deep-mine Ironstone 

 Shale, Longton, K". Staffordshire. Egerton Coll. 



P. 3267. Portions of head, pectoral fin, and anterior abdominal 

 region, partly in counterpart ; Knowles Ironstone Shale, 

 Fenton. JEnnisTcitten Coll. 



P. 3266. Imperfect head, with pectoral fin and anterior scales; 

 Low Main Seam, Newsham, near J^ewcastle-upon-Tyne. 



Enniskillen Coll. 



P. 5195. Portions of head, pectoral fin, and anterior scales ; Dale- 

 moor Rake Ironstone, Stanton-by-Dale, Derbyshire. 



Purchased, 1885. 



