TRIASSIC FISHES FROM SPITZBERGEN 
3oj 
Explanation of index letters. 
Alsph, alisphenoid fused with and forming a process from the fronto-dermosphenotic; D 2, ante¬ 
rior dorsal fin; Fr. dsph, fronto-dermosphenotic; Op, operculum; Pa. it, parieto-intertemporal; Pc, 
pectoral fin; Psph, parasphenoid (posterior half); Pt, pterygoid (upper part of the posterior limb); 
Qu, quadrate; So, supraorbitals; Sp 2, supporting bone for the anterior dorsal fin; Sp2, supporting 
bone for the posterior dorsal fin; Stemp. ext, supratemporo-extrascapular; Ic, cranial section of the 
lateral canal; s. com, supratemporal cross-commissure given off already within the supratemporo- 
extrascapular. 
Plate 18. 
Fig. 1. Mylacanthus lobatus n. sp., some scales from the specimen (P. 218) in figure 4 of this plate. 2 / 1 . 
» 2. Scleracanthus asper » » parts of metapterygoid (Mptg) und pterygoid (Pt) in medial aspect; 
from specimen P. 24.1a. 
» 3. Mylacanthus? or Scleracanthus? sp., membrane bones on the anterior part of the cranial roof 
(P. ig8). The specimen with the postrostral subdivided into 
one anterior ( Ptri ) and one posterior ( Ptr 2 ) plate. The 
interrostral ( Ir ) probably paired and the rostrals (P) more 
numerous than in Axelia. For the explanations of designa¬ 
tions cf. further Pis. n—14. 
>, 4, » lobatus n. sp., parts of the visceral skeleton of the right side with fragments 
of the shoulder girdle ( Cl and Id). After specimen P. 218. The 
bones partly preserved as impressions in the stones. Among the 
other bones there are seen several of various sizes (Dp), which have 
covered the copula and the gill-arches and which are provided 
with more or less large spiheroid teeth. 
Explanation of index letters. 
Aang, autangular; Cl, cleithral; De , dental; Dp, tooth-bearing plates from the copulae and 
the gill-arches; Fr. dsph , fronto-dermosphenotic; G? jugular plate?; Icl, clavicle; Ir, interrostral; 
Mptg, metapterygoid; Na, ant, nasalo-antorbital; Op, operculum; Pt, pterygoid; P/r^, anterior post¬ 
rostral plate; Ptr2, posterior postrostral plate; Qu, quadrate; R, rostrals; Sang, ang, supraangulo- 
angular; Spl, splenial; p, pores of the mandibular sensory canal. 
Plate 19. 
Fig. 1. Scleracanthus asper n. sp., parts of the visceral skeleton of the right side together with the 
ventral limbs of the clavicles (Icl) of specimen P. 240. The 
bones partly as impressions of the external side. Aang, autan¬ 
gular; Art.? possibly articular in section; G , jugular plate; 
Sang, ang , supraangulo-angular; Scrp, sclerotic plate; me, poste¬ 
rior portion of the mandibular sensory canal and p, a number 
of pores of this canal. 
» 2. » » » » scale (P. 242a). 2 / r 
» 3. Mylacanthus spinosus? n. sp., parts of the visceral skeleton and a fragment of the para¬ 
sphenoid (Psph) of specimen P. 2r5. 
Explanation of index letters. 
Aang, autangular; Art.? possibly articular; De, dental; Dp, tooth-bearing plate, probably one 
of those which have covered the copular series; G, jugular plate; Icl, clavicle (in fig. 1, only the 
ventral limb preserved); Psph , parasphenoid; Sang, ang, supraangulo-angular; Scrp, sclerotic plate; 
Spl, splenial; me, mandibular sensory canal; p, pores of the mandibular sensory canal. 
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