124 OLD RED SANDSTONE FISHES. 



flaked off the impression of the outer sculpture is seen on the stone. From this 

 impression it is clear that there was no median carina. 



Other plates found in a more or less fragmentary condition on the few slabs 

 showing remains of this species in the Royal Scottish Museum, are the anterior 

 median dorsal, which, like the posterior one, seems to have no median carina — the 

 anterior and posterior dorso-laterals, and the posterior ventro-lateral — but want of 

 space prevents me from giving figures of them. Their external sculpture agrees 

 with that shown in the figures given in PI. XXIX, while in contour they resemble 

 the plates of B. major. 



Remarks. — The plates of this species were referred by Sir A. Geikie in 1869 and 

 in 1882 to " Pterichthys" major, and in 1888 I also considered them as belonging 

 to the same species, which I placed, however, in Bothriolepis. Subsequent closer 

 study convinced me of their specific distinction, and accordingly in 1892 I 

 separated them under the name of Bothriolepis leptocheirus. 



Geological Position ami Locality. — From the Upper Old Red Sandstone at the 

 Heads of Ayr, Ayrshire, in the collections of the Royal Scottish Museum and of 

 the Geological Survey of Scotland. In the latter collection there are also an 

 anterior dorso-lateral plate and some other fragments from the same formation at 

 Siccar Point, Berwickshire, which are, in my opinion, also referable to this species. 



Bothiuolepis hydeophila, Agassi::, sp. Plate XXX, figs. 1 — 3. 



1844. Pterichthys hydrophilus, Agassiz. Poiss. Foss. v. Gres rouge, Atlas, 



pi. iv, figs. 4 — 6. 

 Pamphractus — Agassiz. Ibid., text pp. 5 and 21. 



Andersoni, Agassiz. Ibid., p. 21. 



1845. Homo-thorax Flemingii, Agassiz. Ibid., p. 134, pi. xxxi, fig. 6. 



1848. Pterichthys hydrophilus, Egerton and Hugh Miller. Quart. Journ. G-eol, 



Soc, vol. iv, pp. 812, 314. 

 1859. Pamphractus Andersoni = Pterichthys hydrophilus, /. Anderson. 



Dura Den, pp. 49, 52, pi. i, fig. 1. 

 1862. Pterichthys hydrophilus, ./. Powrie. Quart. Journ. Geo!. Sue., vol. xviii. 



p. 1.35. 

 1888. Bothriolepis hydrophilus, E, H. Trdquair. Geol. Mag. (3), vol. 5, p. 510, 



and Aim. and Mag. Nat. Hist, (6) 

 vol. ii. p. 500. pi. xviii, figs. 4, 5. 

 L891. bydrophila, ,1. 8. Woodward. Cat. Foss. Fishes Brit, 



Mus.. pt. ii, p. 280. 



Specific Characters.- Length of head contained three times in the total id' the 



