Trof. Traqua'ir — On a New Fossil Fish. 553 



snout ; an anterior margin forming the front edge of the upper lip : 

 and an inferior excavated surface, which formed part of the roof of 

 the mouth and nasal chambers. Placing the snout in its natural 

 position, with the labial margin horizontal (PL XIV. Fig. 3), the 

 superior surface is seen to slope downwards and forwards in the 

 middle line at an angle of 45°, while towards the sides it is 

 rounded off in an arched manner. This surface shows no trace 

 either of sutures or of external nasal openings ; it is smooth and 

 ganoid, glossy and finely reticulate-punctate : near the labial margin, 

 however, the minute punctures disappear, and are replaced by another 

 set, which are larger, fewer, and further apart. Many of these larger 

 punctures are also seen on the finely-reticulate surface above. 



On turning up the fossil, and looking at it from below (Fig. 2), we 

 see first a flattened margin, situated in front and laterally, which 

 must have formed part of the upper lip, and which passes by a 

 rounded edge over to the upper surface just described. This labial 

 margin is brilliantly polished, and ornaniented with the large 

 scattered punctures already alluded to, and which average about -L. 

 inch in diameter. It shows also on each side and internally a pretty 

 deep rounded notch, clearly indicating the position of an anterior 

 nasal opening, which must thus have penetrated the upper lip as in 

 the living Dipnoi. This arrangement also agrees perfectly with 

 what is seen on the under aspect of the snout of Dipterus. The 

 portion of the labial margin situated between the right and left nasal 

 notches shows a faint median indentation, dividing it into two parts, 

 and each of those parts, right and left, is set on its rounded posterior 

 edge .with a row of six small blunted tooth-like projections. Similar 

 blunted tooth-like bodies are also seen on the inner aspect of the 

 projecting portion of the labial margin behind each nasal notch. 



Posteriorly and internal to this strange ganoid labial margin, the 

 specimen is deeply excavated, and the surface here seen has evidently 

 formed part of the roof of the nasal chambers on each side, and of 

 the front of the roof of the mouth. The bone is here rough; no 

 sutures can be distinguished; but the median longitudinal projecting 

 portion evidently represents the front of the vomer, anterior to the 

 attachment of the palato-ptei'ygoid plates. No trace is seen of 

 vomerine teeth, as in Ceratodus and Lepidosiren, nor of their places 

 of attachment as noticed by Giinther in Dipterus ; if present in this 

 fish, they must also have been posterior to the portion preserved, 



The hinder margin, all the way across between the two posterior 

 angles of the specimen, shows nothing but the rough fractured sur- 

 face where it has been broken off from the rest of the head. How- 

 ever, we may see here that the bone, forming the surfaces just 

 described, exists as a rather thin shell over an internal space once 

 occupied beyond doubt by cartilage, now completely filled up by 

 the stony matrix, a dull grey argillaceous limestone. But the part 

 between the posterior angle of the specimen, on each side, and the 

 boss-like dentigerous projection behind each nasal notch, shows a 

 distinct articular surface looking backwards, and which may have 

 been for a maxillary bone, or for a superficial facial bone if the 



