TRIASSIC FISHES FROM SPITZBERGEN 
295 
Fig. 15. Palaeobates polaris n. sp., tooth, possibly from row b, in medial aspect (P. 107). Showing 
the relations between the masticatory surface and the baso-me- 
dially directed surface of the crown. 2 /j. 
» 16. » » » » left mandible (b) and counterpart (a) with the left ceratohyal 
(chy ) and five transversal rows of teeth ( a — c) in situ ( P.107 ). 1 L. 
Figs. 17—18. Palaeobates polaris n. sp. Teeth in transverse section (P. 107) p, pulp cavity. Enamel 
not visible in the sections. 3 / 1 . 
Fig. 19 a—d. Ceratodus sp. right mandibular tooth in section (a) in medial (b) in dorsal (c) and 
in ventral (cf) aspects (P. g 5 o). k, contact surface by which the tooth has 
met that of the opposite side (referred to in the text as surface a). 1 ] 1 . 
Plate 4. 
Fig. 1. Wimania sinuosa n. sp., head from the right side with the cheek plates and parts of the 
cranial roof removed (P. 207). 
» 2. Wimania sinuosa n. sp., the same head seen from the left side. 
Explanation of index letters. 
Aang, autangular; Alsph, alisphenoid fused with and forming a ventral process from the fronto- 
dermosphenotic; Aup, autopalatine; Br, ceratobranchial; Bsph, basisphenoid; Chy, ceratohyal; Fr. 
dsph, fronto-dermosphenotic; Icor. pra, intercoronoideo-prearticular; Mptg, metapterygoid; Op, oper¬ 
culum; Pa. it, parieto-intertemporal (represented by the posterior part of the ventral longitudinal 
lamella); Psph, parasphenoid (anterior end); Pt, pterygoid; Ptr , postrostral; Qu, quadrate; Stemp. 
ext, supratemporo-extrascapular; tJhy, urohyal; al, paired forward-pointing lamella from the basi¬ 
sphenoid corpus; e, basipterygoid process; f, anterior end of the prootico-opisthotic; f x , dorsal 
process from the prootico-opisthotic (dorsal end); h, antero-ventral process from the supratemporo- 
extrascapular; y, loose bone probably from the shoulder girdle; F 3 , 3 , sinus in the dorso-lateral edge 
of the basisphenoid indicating the exists of the roots for the r. maxillaris trigemini, r. mandibularis 
trigemini, ramus ophthalmicus trigemini, n. buccalis lateralis and n. ophthalmicus lateralis. 
Plate 5. 
Fig. 1. Wimania sinuosa n. sp., the same head (P. 257) as in the preceding plate, seen from above. 
The cranial roof partly imperfectly preserved (posteriorly and on 
the left side). 
» 2. » » » » cheek plates and certain bones from the visceral skeleton of the 
right side. The same specimen as in PI. 4 ( P. 257). 
» 3. » » » » Some remains of scales (P. 255). 3 / 2 . 
» 4. » » » » cheek plates and some bones from the visceral skeleton ot the 
left side. The same specimen as in PI. 4 (P. 257). 
Explanation of index letters. 
Alsph, alisphenoid fused with and forming a ventral process from the fronto-dermosphenotic; 
Aup, autopalatine; Bsph, basisphenoid; Co, coronoid; De, dental; Fr. dsph, fronto-dermosphenotic; 
Icor. pra, intercoronoideo-prearticular; La. ju, lacrymo-jugal; Mptg, metapterygoid (posterior part); 
Mx, maxillary; Na. ant, nasalo-antorbital; Op, operculum; Pa.it, parieto-intertemporal (ventral 
longitudinal lamella); Pco, precoronoid plates; Po, postorbital; Pop. quj, preoperculo-quadratojugal; 
Ptr, postrostral; Scr, sclerotic plates; So, supraorbitals (boundaries between the various elements 
indistinct); Sq.pop, squamoso-preopercular; Stemp. ext, supratemporo-extrascapular; al, paired for- 
