556 EAMSAY H. TRAQT/AIR OX AMBLYPTERTTS, 



suddenly narrowing near the extremity to an acutely pointed apex. 

 Each tooth is also first inclined a little inwards, then bent outwards 

 at an obtuse angle ; finally, by another curvature, the apex conies to 

 point upwards in the mandibular teeth, downwards in those of the 

 maxilla. The teeth are also closely set in one row of nearly 

 uniform size : there are certainly no larger teeth inside this row ; 

 nor have I seen any trace of smaller ones outside. Mr. Walker 

 describes the teeth of the lower jaw of the Pitcorthie fish as 

 " placed alternately one close to the outside margin ; the next to it is 

 fully halt' its own thickness further in, and so on the whole length 

 of the bone." Of this arrangement I have seen nothing more in the 

 Wardie specimens than occasional indications. By Agassiz the 

 teeth of G. punctatus were described as being "en cones obtus," an 

 appearance due to their being only seen in antero-posterior vertical 

 section in the specimen he examined, their peculiar flexures and 

 pointed conical apices being there invisible. Xor do I find any 

 evidence that they were arranged " sur plusieurs rangees," at least 

 as far as the maxilla and dentary of the mandible are concerned, 

 though it is probable that additional teeth were present in the 

 palate. 



The dorsal fin in Gonatodus is placed rather further back than in 

 Eloniehthffs, the middle of its base being opposite the commence- 

 ment of the anal : both dorsal and anal are large and triangular ; 

 the base of the ventrals is short. All the fins are composed of very 

 numerous rays, which are closely jointed, including in that respect 

 also the principal rays of the pectoral. The suspensorium is not so 

 oblique as in most genera of Paheoniscidce, but more so than in 

 Amblypterus. 



A new species of this genus (G. macrolepis, Traq.), characterized 

 by its very large and nearly smooth scales, has recently turned up 

 in the Blackband Ironstone of Gilmerten. As yet the genus is only 

 known from the lower division of the Carboniferous formation in 

 Scotland. 



I regret that I have had no opportunity of forming any indepen- 

 dent opinion as to the affinities of the Triassie species Amblypteras 

 Agassizii of Miinster, A. ornatus and latimanus of Giebel, or of that 

 from the cupriferous sandstones of Kargala in Russia, named A. 

 oriental is by Eichwald. and can only say regarding them that, from 

 the descriptions given, they do not seem to belong to the genus 

 AmbJiipterus as restricted by Troschel. A. Olfersi has been already 

 referred by Agassiz himself to the Teleostean genus Eliacohpis. 



Pal-eoxisccs. 



The genus PaJceoniscus has been made to include an immense 

 number of species, which are, indeed, referable to more than one 

 generic type, some of them actually not being Palaeoniscida? at all. 

 Authors have, in point of fact, been only too apt to refer nearly 

 every small rhombic-scaled fusiform-shaped ganoid fish from Upper 

 Palaeozoic rocks to Palceoniscus, without inquiring too narrowly into 



