GONATODUS MACROLEPIS. 97 



in the front of the body, a greater amount of external ornament, though cases do occur 

 in which they are all nearly devoid of striation. 



Geological Position and Localities. — Scottish Lower Carboniferous, and apparently 

 confined to the "Calciferous Sandstone" Series. Gonatodus punctatus is one of the 

 commonest of the fishes which occur in the ironstone nodules of Wardie Beach near 

 Edinburgh, and in East Lothian it has recently been collected at Gullane by the 

 Geological Survey of Scotland. In Fifeshire, at Pitcorthy near Anstruther. 



Agassiz's type from Wardie is preserved in the Royal Scottish Museum, as are also 

 the specimens from Pitcorthy figured by Walker. 



2. Gonatodus macrolepis, Traquair. Plate XX, figs. 9 — 14; Text-figure 3 b. 



Gonatodus macrolepis, Traquair. Quart. Journ. Geol. Soc.,vol. xxxiii, 1877, p. 



556 ; Proc. Roy. Soc. Ediub., vol. ix, 1877, 

 p. 271, and vol. xvii, 1890, p. 391 ; Trans. 

 Eoy. Soc. Edinb., vol. xl, pt. iii, no. 28, pp. 

 692 and 694. 

 — A. 8. Woodward. Cat. Eoss. Eishes Brit. Mus., pt. ii, 



1891, p. 435, pi. xvi, fig. 8. 



Specific Characters. — Inferior, or dcntary, margin of the maxilla bent suddenly down- 

 wards shortly behind the junction of the sub-orbital process with the post-orbital plate, 

 so that the latter appears proportionally high and broad ; teeth large ; scales large, 

 mostly quite smooth with scattered punctures, and only seldom showing traces of 

 striation along the anterior and inferior borders. 



Description. — The usual length of examples of this species is from four to six or 

 seven inches, but although a considerable number of specimens more or less " perfect " 

 have been found, in no two do the proportional measurements agree owing to the greater 

 or less amount of alteration of form which they have undergone, apparently both soon 

 after death, and during the consolidation of the matrix. Seldom do the scales, save on 

 the caudal body-prolongation, remain in their original relations to each other on any 

 considerable part of the body, but are always more or less jumbled up, even though the 

 contour of the fish may remain tolerably regular, and the shape and structure of the fins 

 be quite intact. This condition affects nearly the whole of the smaller fishes found in 

 the Gilmerton Ironstone, from which bed all the entire specimens of G. macrolepis have 

 been derived. 



The specimen represented in Plate XX, fig. 9, is on the whole the most perfect which 

 I have seen, and measures as it lies Q>\ inches in length, but, were the snout perfect, 

 7 inches would be the correct number. Allowing for the missing snout the length of the 

 head would be contained about five times in the total, and the general shape is, like that 



