134 DR. A. SMITH WOODWARD ON VERTEBRATE [May I907, 



Some larger scales (PI. VI, fig. 5), which are slightly wider than 

 deep, have the same general shape as those just described, with the 

 ascending antero- superior angle; but their oblique keel is less 

 prominent, and is subdivided into a pair of nearly-parallel ridges. 

 These scales are united by a peg-and-socket joint, in which the peg 

 is subdivided into fine digitations at the end ; but their inner face 

 is not strengthened by a vertical keel. The new species may be 

 named Belonostomus (? ) carinatus, in allusion to the peculiar 

 ornamentation and armature of the smaller scales. 



Mawsonia gigas, gen. et sp. nov. (Pis. VII & VIII.) 



Por many years Mr. Mawsou has obtained pieces of coarsely- 

 sculptured bony plates and large fish-bones, especially on the beach 

 near Plataforma ; but, until the recent arrival of the last instal- 

 ment of his collection at the British Museum, it was impossible to 

 interpret these fossils. A large fragmentary skull now furnishes a 

 clue to their true nature, and shows that they represent a gigantic 

 Crossopterygian ganoid of the family Ccelacanthidae. The species 

 may be regarded as referable to a new genus, Maivsonia, with the 

 skull closely similar to that of the European Cretaceous Macropoma, 

 though the external bones are destitute of enamel and ornamented 

 with more or less radiating ridges, which are mainly longitudinal 

 on the cranial roof and angular bone, but diverge from the point of 

 suspension on the operculum. In Maivsonia gigas, as I propose to 

 name the typical species, the angular bone of the mandible measures 

 40 centimetres in length, and is thus four times as large as the 

 largesL Coelacanth angular bone hitherto discovered. 



The skull just mentioned, which must be regarded as the type- 

 specimen of M. gigas, is fragmentary, and distorted by lateral com- 

 pression, but displays very well many of the principal bones. It is 

 shown, of one-third the natural size, from the right side in PI. VII, 

 fig. 1, with drawings of the left frontal and left quadrate bone in 

 figs. 2, 3, and of the left mandibular ramus, articular bone, coronoid 

 bone, pterygoid teeth, and gular plate in PI. VIII, figs. 1-5. The 

 cranium (cr.) has collapsed in the crushing and seems to have been 

 imperfectly ossified, except in the postero- superior part of the otic 

 region (ot.), which is prominent on each side of the fossil. The 

 cranium is underlain by the long and slender parasphenoid {pas.), 

 seen from below in fig. 1, and tapers forward to a broken extremity, 

 which may, or may not, have been continued into an anterior 

 jspatulate end. So far as it is preserved, the oral face of the 

 parasphenoid is toothless, while the hinder portion of its upper face 

 is slightly excavated by a longitudinal channel. Of the cranial roof, 

 only part of the left frontal (PI. VII, fig. 2) is preserved, showing its 

 irregularly-wavy but smooth hinder border, which would articulate 

 with the parietal element. Its outer face is ornamented with 

 longitudinal ridges, which diverge slightly and increase both in 

 strength and in number as they extend forward, but are apparently 

 destitute of an enamel-layer. The right parietal bone (PI. VII, 



