TRIASSIC FISHES FROM SPITZBERGEN 
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Plate 13. 
Axelia robusta n. sp., the same parts of the head (P. ig 5 ) as in the preceding plate but with the 
metapterygoid and a dorsal part of the posterior limb of the pterygoid removed 
to show better the ossifications in the primordial neurocranium. The prootico- 
opisthotic (Pro. 0 ) in this figure, is represented by an imperfect impression 
of the medial'side. 
Explanation of index letters. 
Bsph , basisphenoid (in lateral aspect); Psph, parasphenoid (here only the posterior part seen); 
al, paired forward pointing lamella from the basisphenoid corpus; v, paired ventral process from 
the basisphenoid corpus. 
Other index letters the same as in plates n and 12. 
Plate 14. 
Fig. 1. Axelia robusta n. sp., head seen from above. The same head as in plates 11, 12, i3 
(P. ig 5 ). The external surface of the bones of the dermal cranial 
roof not preserved. 
Figs. 2-3. » » » » The anterior part of the cranial roof and its relations to the 
basisphenoid. Same specimen as in the preceding figure (P. rg 5 ). 
The posterior end for the furrow of the n. ophthalmicus lateralis 
(r. ophth.) clearly seen on the alisphenoid. 
Fig. 4. » » » » The membrane bones on the upper side of she ethmoidal region 
seen from in front. The same specimen as in the figures above 
(P.ig 5 ). 
» 5 » » » » basisphenoid seen from in front. 
After the same specimen as the other figures on this plate and plates 11—13 (P. rg 5 ) 
Bsph, basisphenoid with the anterior ends of the basipterygoid processes (e) and the anterior 
parts of the anteriorly pointing lamella (al) lacking. The fossa bounded by the corpus and 
the anterior pointing lamellae is clearly shown. Parasphenoid in transversal section. 
Explanation of index letters. 
Alsph, alisphenoid fused with and forming a long process from the fronto-dermosphenotic ; 
Bsph, basisphenoid; Ext, extrascapular plates; Fr. dsph, fronto-dermosphenotic; Ir, interrostral; 
Na. ant, nasalo-antorbital; Pa. it, parieto-intertemporal (the part laterally of the ventral lamella not 
preserved); Psph, parasphenoid (in transverse section); Ptr, postrostral; R, rostrals; So, supraorbitals; 
Sscop, suprascapular; Stemp. ext, supratemporo-extrascapular; al, paired anteriorly pointing lamella 
of the basisphenoid; e , basipterygoid process; ifc, infraorbital canal (in the dermosphenotic com¬ 
ponent of the fronto-dermosphenotic); m, myodome; naj and na 2 , nasal apertures; p, pores of the 
supraorbital sensory canal; r, torus on the medial side of each anterior lamella of the sphenoid; 
r. ophth, furrow for the n. ophthalmicus lateralis (posterior end) on the alisphenoid; s, furrow deve¬ 
loped in relation to the hypophysis. Together with cartilage it has formed a vertical canal opening 
in the myodome; v, paired ventral process from the basisphenoid corpus; Vj, longitudinal section 
through the canal for the r. ophthalmicus profundus or a somewhat equivalent nerve. 
Plate 15. 
Figs. 1, 2. Axelia robusta n. sp., parts of the visceral skeleton of the right side (P. i6g ). The 
bones to some extent preserved as impressions of the lateral sur¬ 
face. In fig. 2 a part of the pterygoid (Pi), ceratohyal (Chy) and 
Stensio, Triassic Fishes from Spitzbergen. 3g 
